Performance evaluation method for plasma processing apparatus

ABSTRACT

A plasma processing apparatus has a plasma processing chamber having a plasma excitation electrode, a radiofrequency generator connected to the plasma excitation electrode, and a matching circuit for matching the impedance between the plasma processing chamber and the radiofrequency generator. The loss capacitance C X1  at a later time t 1  after delivery is measured between the plasma excitation electrode and ground potential positions which are grounded. The performance is evaluated by whether or not the loss capacitance C X1  is less than 26 times the plasma electrode capacitance C e1  at the later time t 1  between the plasma excitation electrode and a counter electrode which cooperate with each other.

This is a division of application Ser. No. 10,033,443, filed Nov. 2,2001, now U.S. Pat. No. 6,701,202.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a plasma processing apparatusand system, a performance evaluation method therefor, a maintenancemethod therefor, a performance management system therefor, and aperformance validation system therefor. More particularly, the presentinvention is directed to a technology suitable for ensuring that theplasma processing apparatus and system maintain the required level ofperformance even after the delivery of the apparatus and system tocustomers.

2. Description of the Related Art

FIG. 38 illustrates an example of a conventional dual-frequencyexcitation plasma processing apparatus which performs a plasma processsuch as a chemical vapor deposition (CVD) process, a sputtering process,a dry etching process, or an ashing process.

In the plasma processing apparatus shown in FIG. 38, a matching circuit2A is connected between a radiofrequency generator 1 and a plasmaexcitation electrode 4. The matching circuit 2A matches the impedancesof the radiofrequency generator 1 and the excitation electrode 4.

Radiofrequency power from the radiofrequency generator 1 is fed to theplasma excitation electrode 4 via the matching circuit 2A and a feedplate 3. The matching circuit 2A is accommodated in a matching box 2which is a housing composed of a conductive material. The plasmaexcitation electrode 4 and the feed plate 3 are covered by a chassis 21made of a conductor.

The plasma excitation electrode 4 is provided with a projection 4 a atthe bottom face thereof. A shower plate 5 having many holes 7 providedunder the plasma excitation electrode 4 is in contact with theprojection 4 a. The plasma excitation electrode 4 and the shower plate 5define a space 6. A gas feeding tube 17 composed of a conductivematerial is connected to the space 6. The gas feeding tube 17 isprovided with an insulator 17 a at the middle thereof so as to insulatethe plasma excitation electrode 4 and the gas source.

Gas from the gas feeding tube 17 is fed inside a plasma processingchamber 60 comprising a chamber wall 10, via the holes 7 in the showerplate 5. An insulator 9 is disposed between the chamber wall 10 and theplasma excitation electrode 4 (cathode) to provide insulationtherebetween. The exhaust system is omitted from the drawing.

A wafer susceptor (susceptor electrode) 8 which receives a substrate 16and also serves as another plasma excitation electrode is installedinside the plasma processing chamber 60. A susceptor shield 12 isdisposed under the wafer susceptor 8.

The susceptor shield 12 comprises a shield supporting plate 12A forsupporting the susceptor electrode 8 and a supporting cylinder 12Bextending downward from the center of the shield supporting plate 12A.The supporting cylinder 12B extends through a chamber bottom 10A, andthe lower portion of the supporting cylinder 12B and the chamber bottom10A are hermetically sealed with bellows 11.

The shaft 13 and the susceptor electrode 8 are electrically isolatedfrom the susceptor shield 12 by a gap between the susceptor shield 12and the susceptor electrode 8 and by insulators 12C provided around theshaft 13. The insulators 12C also serve to maintain high vacuum in theplasma processing chamber 60. The susceptor electrode 8 and thesusceptor shield 12 can be moved vertically by the bellows 11 in orderto control the distance between plasma excitation electrodes 4 and 8.

The susceptor electrode 8 is connected to a second radiofrequencygenerator 15 via the shaft 13 and a matching circuit accommodated in amatching box 14. The chamber wall 10 and the susceptor shield 12 havethe same DC potential.

FIG. 39 illustrates another example of a conventional plasma processingapparatus. Unlike the plasma processing apparatus shown in FIG. 38, theplasma processing apparatus shown in FIG. 39 is of a single-frequencyexcitation type. In other words, a radiofrequency power is supplied onlyto the electrode 4 while the susceptor electrode 8 is grounded.Moreover, the matching box 14 and the second radiofrequency generator 15shown in FIG. 38 are not provided. The susceptor electrode 8 and thechamber wall 10 have the same DC potential.

In these plasma processing apparatuses, power with a frequency ofapproximately 13.56 MHz is generally supplied in order to generate aplasma between the electrodes 4 and 8. A plasma process such as aplasma-enhanced CVD process, a sputtering process, a dry etchingprocess, or an ashing process is then performed using the plasma.

The power consumption efficiency, i.e., the ratio of the power consumedin the plasma to the power supplied to the plasma excitation electrode4, of these plasma processing apparatuses has been poor. Especially asthe frequency supplied from the radiofrequency generator is elevated,the power consumption efficiency of the plasma processing apparatus hasdecreased significantly. Moreover, use of large size substrates hascaused the power consumption efficiency to further decrease.

As a result, conventional plasma processing apparatuses have sufferedfrom low deposition rate as a result of failing to increase theeffective power consumed in the plasma space due to a low powerconsumption efficiency. When applied to a deposition process, forexample, insulating layers with high isolation voltage can barely beformed.

The operation validation and performance evaluation of theabove-described plasma processing apparatuses have been conducted byactually performing the process such as deposition and then evaluatingthe deposition characteristics thereof according to followingProcedures:

Procedure (1) Deposition Rate and Planar Uniformity

Step 1: Depositing a desired layer on a 6-inch substrate by aplasma-enhanced CVD process.

Step 2: Patterning a resist layer.

Step 3: Dry-etching the layer.

Step 4: Removing the resist layer by ashing.

Step 5: Measuring the surface roughness using a contact displacementmeter to determine the layer thickness.

Step 6: Calculating the deposition rate from the deposition time and thelayer thickness.

Step 7: Measuring the planar uniformity at 16 points on the substratesurface.

Procedure (2) BHF Etching Rate

A resist mask is patterned as in Steps 1 and 2 in (1) above.

Step 3: Immersing the substrate in a buffered hydrofluoric acid (BHF)solution for one minute to etch the layer.

Step 4: Rinsing the substrate with deionized water, drying thesubstrate, and separating the resist mask using a mixture of sulfuricacid and hydrogen peroxide (H₂SO₄+H₂O₂).

Step 5: Measuring the surface roughness as in Step 5 in Procedure (1) todetermine the layer thickness after the etching.

Step 6: Calculating the etching rate from the immersion time and thereduced layer thickness.

Procedure (3) Isolation Voltage

Step 1: Depositing a conductive layer on a glass substrate by asputtering method and patterning the conductive layer to form a lowerelectrode.

Step 2: Depositing an insulating layer by a plasma-enhanced CVD method.

Step 3: Forming an upper electrode as in Step 1.

Step 4: Forming a contact hole for the lower electrode.

Step 5: Measuring the current-voltage characteristics (I-Vcharacteristics) of the upper and lower electrodes by using probes whileapplying a voltage up to approximately 200 V.

Step 6: Defining the isolation voltage as the voltage V at 100 pAcorresponding 1 μA/cm² in a 100 μm square electrode.

The plasma processing apparatus for use in manufacturing semiconductorsand liquid crystal displays has been required to achieve a higher plasmaprocessing rate (the deposition rate or the processing speed), increasedproductivity, and improved planar uniformity of the plasma processing(uniformity in the distribution of the layer thickness in a planardirection and uniformity in the distribution of the process variation inthe planar direction). As the size of substrates has been increasing inrecent years, the requirement of planar uniformity has become tighter.

Moreover, as the size of the substrate is increased, the power requiredis also increased to the order of kilowatts, thus increasing the powerconsumption. Accordingly, as the capacity of the power supply increases,both the cost for developing the power supply and the power consumptionduring the operation of the apparatus are increased. In this respect, itis desirable to reduce the operation costs.

Furthermore, an increase in power consumption leads to an increase inemission of carbon dioxide which places a burden on the environment.Since the power consumption is increased by the combination of increasein the size of substrates and a low power consumption efficiency,reduction of the carbon dioxide emission is desired.

The power consumption efficiency is known to be improved by increasingthe plasma excitation frequency. For example, a frequency in the VHFband of 30 MHz or more can be used to improve the efficiency instead ofthe conventional 13.56 MHz. Thus, one possible way to improve thedeposition rate of a deposition apparatus such as a plasma-enhanced CVDapparatus is to employ a higher plasma excitation frequency.

In a plasma processing apparatus having a plurality of theabove-described plasma processing chambers, i.e., a multi-chamber plasmaprocessing apparatus, variation in plasma processing among the plasmaprocessing chambers is required to be reduced so that the plasmaprocessing rate (deposition rate when applied to a deposition process),productivity, and uniformity in the plasma process in the planardirection of a workpiece (planar distribution in the layer thickness)can be made substantially the same among the workpieces plasma-treatedin different plasma processing chambers.

The plasma processing apparatus is also required to yield substantiallythe same process results by applying the same process recipe specifyingexternal parameters for respective plasma processing chambers such asgas flow, gas pressure, power supply, and process time.

During installation or maintenance of the plasma processing apparatus,reduction in the time required for adjusting the plasma processingapparatus to achieve substantially the same process results by applyingthe same recipe and eliminate the variation among the plurality ofplasma processing chambers has been desired. Also, reduction in the costrequired for such adjustment has been desired.

Furthermore, in a plasma processing system comprising a plurality ofplasma processing apparatuses, improvement in the uniformity in plasmaprocess results among the plasma processing chambers of the apparatuseshas also been desired.

The above-described plasma processing chamber is designed to use powerwith a frequency of approximately 13.56 MHz and is not suited for powerof higher frequencies. Specifically, radiofrequency characteristics suchas capacitance, impedance, and resonant frequency characteristics of theplasma processing chamber as a whole have been neglected; consequently,no improvement in the electrical consumption efficiency has beenachieved even when power of a frequency higher than approximately 13.56MHz is employed, resulting in decrease in the deposition rate ratherthan improvement. Moreover, although the effective power consumed in theplasma space increases as the frequency increases, the effective powerstarts to decrease once its peak value is reached, eventually reaching alevel at which glow-discharge is no longer possible, thus renderingfurther increases in frequency undesirable.

Conventional plasma processing apparatuses suffer from the followingdisadvantages.

Conventional plasma processing apparatuses and systems are not designedto eliminate the differences in electrical radiofrequencycharacteristics such as impedance and resonant frequency characteristicsamong the plasma processing chambers constituting the plasma processingapparatus or system. Thus, the effective power consumed in the plasmagenerating spaces of the plasma processing chambers varies betweendifferent plasma processing chambers.

As a consequence, uniformity in plasma process results are barelyachieved even when the same process recipe is applied to these plasmaprocessing chambers.

In order to obtain uniform plasma process results, external parameterssuch as gas flow, gas pressure, power supply, process time, and the likemust be compared with the process results according to Procedures (1) to(3) described above for each of the plasma processing chambers so as todetermine the correlation between them. However, the amount of datarequired in such a process is enormous and it is impossible tocompletely carry out the comparison.

Moreover, in order to validate and evaluate the operation of the plasmaprocessing apparatus using Procedures (1) to (3) above, the plasmaprocessing apparatus needs to be operated and deposited substrates needto be examined by an ex-situ inspecting method requiring many steps.

Such an inspection requires several days to several weeks to yieldevaluation results, which is significantly long especially when theapparatus is still in development stage. Reduction in time required forobtaining the results has been desired.

Moreover, when Procedures (1) to (3) described above are employed toinspect the plasma processing units constituting the plasma processingapparatus or system, the time required for adjusting the plasmaprocessing units so as to eliminate the difference in performance andvariation in processing among the plasma processing chambers to achievethe same process results using the same process recipe may be months.The time required for such adjustment needs to be reduced. Also, thecost of substrates for inspection, the cost of processing the substratesfor inspection, the labor cost for workers involved with the adjustment,and so forth are significantly high.

As described above, while the plasma processing apparatus is required toachieve a desired performance level, a multi-chamber plasma processingapparatus and a plasma processing system having the plurality of plasmaprocessing chambers are required to eliminate the differences in theperformance of plasma process among the plurality of plasma processingchambers.

Even if the plasma processing apparatus has once been optimized asabove, the plasma processing apparatus is generally disassembled beforethe transfer and then reassembled at the customer site. Thus, it ispossible that the performance is not maintained at the level maintainedbefore the transfer due to the vibration during the transfer andinappropriate reassembly work.

Moreover, the performances of the plasma processing chambers woulddeviate from the required performance level and would exhibit variationin the performance among the plasma processing chambers as plasmaprocesses are repeated in the plasma processing apparatus afterreassembly of the plasma processing apparatus. Also, when an adjustmentwork such as overhaul, parts replacement, and assembly with alignment isperformed, the plasma processing apparatus may not be maintained at adesired level due to inappropriate adjustment or the like.

When Procedures (1) to (3) described above are employed to evaluatewhether the operation of the plasma processing apparatus and thedifference among the plasma processing chambers are maintained withinthe required levels, it becomes necessary to actually operate the plasmaprocessing apparatus and to examine the treated substrates using anex-situ inspection method requiring a plurality of steps.

If the performance of the plasma processing apparatus does not satisfythe required levels, long series of cycle of adjusting the plasmaprocessing apparatus, performing a plasma process on a substrate, andevaluating the processed substrate needs to be repeated, therebyextending the initialization process of the delivered plasma processingapparatus. The length of the time required to complete theinitialization process of a production line directly affects the annualsales.

Thus, it is desired that the validation of the performance of the plasmaprocessing apparatus be performed more easily and that the cycle offault detection and performance of corrective action be performed in ashorter period of time, so as to shorten the initialization process ofthe plasma processing apparatus.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method for easilyand rapidly evaluating whether a plasma processing apparatus or systemis maintained at a required level of performance.

Another object of the present invention is to provide a maintenancemethod for easily and rapidly correcting the plasma processing apparatusor system not maintained at the required level of the performance.

Still another object of the present invention is to provide aperformance management system for a plasma processing apparatus orsystem which maintains the performance of the apparatus or system at therequired level and provides rapid maintenance services when theperformance thereof does not satisfy the required level.

Yet another object of the present invention is to provide a plasmaprocessing apparatus capable of being readily maintained at the requiredlevel of performance.

According to an aspect of the present invention, in a performanceevaluation method for a plasma processing apparatus, the plasmaprocessing apparatus comprising: a plasma processing chamber including aplasma excitation electrode for exciting a plasma; a radiofrequencyfeeder, the plasma excitation electrode being connected to the outputend of the radiofrequency feeder; a radiofrequency generator forsupplying a radiofrequency voltage to the plasma excitation electrode;and a matching circuit having an input terminal and an output terminal,the input terminal being connected to the radiofrequency generator andthe output terminal being connected to the input end of theradiofrequency feeder so as to achieve impedance matching between theplasma processing chamber and the radiofrequency generator, the methodcomprises calculating the absolute value of the difference ΔC_(X)between a loss capacitance C_(X0) at a time t₀ and a loss capacitanceC_(X1) at a later time t₁ of the plasma processing chamber, the losscapacitances C_(X0) and C_(X1) being measured between the plasmaexcitation electrode and ground potential positions which areDC-grounded; and determining that the plasma processing apparatusmaintains a required level of performance when the absolute value isless than an upper limit and that the plasma processing apparatus doesnot maintain the required level of performance when the absolute valueis not less than the upper limit.

Preferably, the upper limit is 10% of the loss capacitance C_(X0). Morepreferably, the upper limit is 3% of the loss capacitance C_(X0).

According to another aspect of the present invention, a maintenancemethod for a plasma processing apparatus is provided, wherein, when theabsolute value of the difference ΔC_(X) is not less than the upper limitin the above performance evaluation method, a corrective action for theloss capacitance C_(X) is performed.

According to another aspect of the present invention, in a performancemanagement system for at least one plasma processing apparatus, theplasma processing apparatus comprising: a plasma processing chamberincluding a plasma excitation electrode for exciting a plasma; aradiofrequency feeder, the plasma excitation electrode being connectedto the output end of the radiofrequency feeder; a radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrode; and a matching circuit having an input terminaland an output terminal, the input terminal being connected to theradiofrequency generator and the output terminal being connected to theinput end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chamber and the radiofrequencygenerator, the performance management system comprises a server forstoring a loss capacitance C_(X0) at a time t₀ between the plasmaexcitation electrode and ground potential positions which areDC-grounded; and a customer I/O device linked to the server via acommunication line, wherein the server receives a loss capacitanceC_(X1) at a later time t₁ between the plasma excitation electrode andthe ground potential positions from the customer I/O device, calculatesthe absolute value of the difference ΔC_(X) between the loss capacitanceC_(X0) and loss capacitance C_(X1), and transmits a signal indicatingthat a required level of performance is maintained when the absolutevalue is less than an upper limit and a signal indicating that therequired level of performance is not maintained when the absolute valueis not less than the upper limit to the customer I/O device.

According to another aspect of the present invention, in a performancemanagement system for at least one plasma processing apparatus, theplasma processing apparatus comprising: a plasma processing chamberincluding a plasma excitation electrode for exciting a plasma; aradiofrequency feeder, the plasma excitation electrode being connectedto the output end of the radiofrequency feeder; a radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrode; and a matching circuit having an input terminaland an output terminal, the input terminal being connected to theradiofrequency generator and the output terminal being connected to theinput end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chamber and the radiofrequencygenerator, the performance management system comprises a server forstoring a loss capacitance C_(X0) at a time t₀ between the plasmaexcitation electrode and ground potential positions which areDC-grounded and service engineer information according to fault levelseach having a predetermined range; an output device for the server, theoutput device being located at a delivery site; and a customer I/Odevice linked to the server via a communication line, wherein the serverreceives a loss capacitance C_(X1) at a later time t₁ between the plasmaexcitation electrode and the ground potential positions from thecustomer I/O device, calculates the absolute value of the differenceΔC_(X) between the loss capacitance C_(X0) and the loss capacitanceC_(X1), and outputs a fault level, service engineer informationcorresponding to the fault level, and a maintenance commandcorresponding to the fault level, when the absolute value falls withinthe fault level with the predetermined range.

According to another aspect of the present invention, a plasmaprocessing apparatus comprises a plasma processing chamber including aplasma excitation electrode for exciting a plasma; a radiofrequencyfeeder, the plasma excitation electrode being connected to the outputend of the radiofrequency feeder; a radiofrequency generator forsupplying a radiofrequency voltage to the plasma excitation electrode;and a matching circuit having an input terminal and an output terminal,the input terminal being connected to the radiofrequency generator andthe output terminal being connected to the input end of theradiofrequency feeder so as to achieve impedance matching between theplasma processing chamber and the radiofrequency generator, wherein theabsolute value of the difference ΔC_(X) between a loss capacitanceC_(X0) at a time t₀ and a loss capacitance C_(X1) at a later time t₁ ismaintained to be less than an upper limit wherein the loss capacitancesC_(X0) and C_(X1) are measured between the plasma excitation electrodeand ground potential positions which are DC-grounded.

According to another aspect of the present invention, a performancevalidation system for the above plasma processing apparatus comprises acustomer terminal, an engineer terminal, and information providingmeans, wherein the customer terminal requests browsing of performanceinformation at the time t₀ and the later time t₁ of the plasmaprocessing apparatus to the information providing means via a publicline, the performance information is uploaded by a maintenance engineerto the information providing means through the engineer terminal, andthe information providing means provides the performance informationuploaded from the engineer terminal to the customer terminal upon therequest from the customer terminal.

In the above aspects, the following actions performed between the timet₀ and the later time t₁ may affect the loss capacitance C_(X);workpiece is introduced into the plasma processing chamber toplasma-treat the workpiece; an adjustment work including overhaul, partsreplacement, and assembly with alignment of the plasma processingchamber is performed; and disassembly, transfer, and reassembly of theplasma processing chamber are performed.

Preferably, in the above aspects regarding the performance managementsystem, the server stores the loss capacitance C_(X0) for theidentification number of the plasma processing apparatus, receives theloss capacitance C_(X1) with the identification number, and calculatesthe difference ΔC_(X).

Preferably, the performance management system according to one of theabove aspects further comprises a measuring device for measuring thecapacitance, the measuring device being connected to both the plasmaprocessing apparatus and the customer I/O device so that the losscapacitance C_(X1) is directly transmitted from the measuring device tothe server.

Preferably, the server comprises an output device at a delivery site,the output device outputting a maintenance command when the absolutevalue of the difference ΔC_(X) is not less than the upper limit.

Preferably, the server transmits the fault level to the customer I/Odevice.

In the above plasma processing apparatus, the absolute value of thedifference ΔC_(X) is preferably maintained to be less than the upperlimit by performing a corrective action of the plasma electrodecapacitance when the absolute value of the difference ΔC_(X) is not lessthan the upper limit.

In the above performance validation system, the performance informationpreferably includes the loss capacitance C_(X). Furthermore, theperformance information may be output as a catalog or specifications.

According to another aspect of the present invention, in a performanceevaluation method for a plasma processing apparatus which isdisassembled before transfer, is transported to a customer, and isreassembled at a customer site, the plasma processing apparatuscomprising: a plasma processing chamber including a plasma excitationelectrode for exciting a plasma; a radiofrequency feeder, the plasmaexcitation electrode being connected to the output end of theradiofrequency feeder; a radiofrequency generator for supplying aradiofrequency voltage to the plasma excitation electrode; and amatching circuit having an input terminal and an output terminal, theinput terminal being connected to the radiofrequency generator and theoutput terminal being connected to the input end of the radiofrequencyfeeder so as to achieve impedance matching between the plasma processingchamber and the radiofrequency generator, the method comprisesdetermining that the plasma processing apparatus maintains a requiredlevel of performance when a loss capacitance C_(X1) of the plasmaprocessing chamber after the delivery is less than 26 times a plasmaelectrode capacitance C_(e1) and that the plasma processing apparatusdoes not maintain the required level of performance when the losscapacitance C_(X1) is not less than 26 times the plasma electrode losscapacitance C_(e1), wherein the loss capacitance C_(X1) is measuredbetween the plasma excitation electrode and ground potential positionswhich are DC-grounded and the plasma electrode capacitance C_(e1) ismeasured between the plasma excitation electrode and a counter electrodewhich generate a plasma in cooperation with each other.

According to another aspect of the present invention, in a performanceevaluation method for a plasma processing apparatus which isdisassembled before transfer, is transported to a customer, and isreassembled at a customer site, the plasma processing apparatuscomprising: a plurality of plasma processing chambers including plasmaexcitation electrodes for exciting plasma; radiofrequency feeders, eachplasma excitation electrode being connected to the output end of thecorresponding radiofrequency feeder; at least one radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrodes; and at least one matching circuit having an inputterminal and an output terminal, the input terminal being connected tothe radiofrequency generator and the output terminal being connected tothe input end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chambers and the radiofrequencygenerator, the method comprises determining that the plasma processingapparatus maintains a required level of performance when a variationC_(e1r), defined by (C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)) betweenthe maximum capacitance C_(e1max) and the minimum capacitance C_(e1min)among plasma electrode capacitances C_(e1) of the plurality of plasmaprocessing chambers is less than an upper limit and that the plasmaprocessing apparatus does not maintain the required level of performancewhen the variation is not less than the upper limit, wherein the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode and a counter electrode which generate a plasma in cooperationwith each other; and determining that the plasma processing apparatusmaintains a required level of performance when a variation C_(X1r),defined by (C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between themaximum capacitance C_(X1max) and the minimum capacitance C_(X1min)among loss capacitances C_(X1) of the plurality of plasma processingchambers is less than an upper limit and that the plasma processingapparatus does not maintain the required level of performance when thevariation is not less than the upper limit, wherein the loss capacitanceC_(X1) is measured between the plasma excitation electrode and groundpotential positions which are DC-grounded.

According to another aspect of the present invention, in a performanceevaluation method for a plasma processing apparatus which isdisassembled before transfer, is transported to a customer, and isreassembled at a customer site, the plasma processing apparatuscomprising: a plurality of plasma processing chambers including plasmaexcitation electrodes for exciting plasma; radiofrequency feeders, eachplasma excitation electrode being connected to the output end of thecorresponding radiofrequency feeder; at least one radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrodes; and at least one matching circuit having an inputterminal and an output terminal, the input terminal being connected tothe radiofrequency generator and the output terminal being connected tothe input end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chambers and the radiofrequencygenerator, the method comprises determining that the plasma processingapparatus maintains a required level of performance when a variationC_(e1r), defined by (C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)), betweenthe maximum capacitance C_(e1max) and the minimum capacitance C_(e1min)among plasma electrode capacitances C_(e1) of the plurality of plasmaprocessing chambers is less than an upper limit and that the plasmaprocessing apparatus does not maintain the required level of performancewhen the variation is not less than the upper limit, wherein the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode and a counter electrode which generate a plasma in cooperationwith each other; and determining that the plasma processing apparatusmaintains a required level of performance when a variation C_(X1r),defined by (C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between themaximum capacitance C_(X1max) and the minimum capacitance C_(X1min)among loss capacitances C_(X1) of the plurality of plasma processingchambers is less than an upper limit and when all the loss capacitancesC_(X1) are less than 26 times the plasma electrode capacitance C_(e1)and that the plasma processing apparatus does not maintain the requiredlevel of performance when the variation is not less than the upper limitor when one of the loss capacitances C_(X1) is not less than 26 timesthe plasma electrode capacitance C_(e1), wherein the loss capacitanceC_(X1) is measured between the plasma excitation electrode and groundpotential positions which are DC-grounded.

According to another aspect of the present invention, in a performanceevaluation method for a plasma processing system which is disassembledbefore transfer, is transported to a customer, and is reassembled at acustomer site, the plasma processing system comprising a plurality ofplasma processing apparatuses, each comprising: a plasma processingchamber including a plasma excitation electrode for exciting a plasma; aradiofrequency feeder, the plasma excitation electrode being connectedto the output end of the radiofrequency feeder; a radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrode; and a matching circuit having an input terminaland an output terminal, the input terminal being connected to theradiofrequency generator and the output terminal being connected to theinput end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chamber and the radiofrequencygenerator, the method comprises determining that the plasma processingsystem maintains a required level of performance when a variationC_(e1r), defined by (C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)) betweenthe maximum capacitance C_(e1max) and the minimum capacitance C_(e1min)among plasma electrode capacitances C_(e1) of the plurality of plasmaprocessing apparatuses is less than an upper limit and that the plasmaprocessing system does not maintain the required level of performancewhen the variation is not less than the upper limit, wherein the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode and a counter electrode which generate a plasma in cooperationwith each other; and determining that the plasma processing systemmaintains a required level of performance when a variation C_(X1r),defined by (C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between themaximum capacitance C_(X1max) and the minimum capacitance C_(X1min)among loss capacitances C_(X1) of the plurality of plasma processingapparatuses is less than an upper limit and that the plasma processingsystem does not maintain the required level of performance when thevariation is not less than the upper limit, wherein the loss capacitanceC_(X1) is measured between the plasma excitation electrode and groundpotential positions which are DC-grounded.

According to another aspect of the present invention, in a performanceevaluation method for a plasma processing system which is disassembledbefore transfer, is transported to a customer, and is reassembled at acustomer site, the plasma processing system comprising a plurality ofplasma processing apparatuses, each comprising: a plasma processingchamber including a plasma excitation electrode for exciting a plasma; aradiofrequency feeder, the plasma excitation electrode being connectedto the output end of the radiofrequency feeder; a radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrode; and a matching circuit having an input terminaland an output terminal, the input terminal being connected to theradiofrequency generator and the output terminal being connected to theinput end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chamber and the radiofrequencygenerator, the method comprises determining that the plasma processingsystem maintains a required level of performance when a variationC_(e1r), defined by (C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)) betweenthe maximum capacitance C_(e1max) and the minimum capacitance C_(e1min)among plasma electrode capacitances C_(e1) of the plurality of plasmaprocessing apparatuses is less than an upper limit and that the plasmaprocessing system does not maintain the required level of performancewhen the variation is not less than the upper limit, wherein the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode and a counter electrode which generate a plasma in cooperationwith each other; and determining that the plasma processing apparatusmaintains a required level of performance when a variation C_(X1r),defined by (C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between themaximum capacitance C_(X1max) and the minimum capacitance C_(X1min)among loss capacitances C_(X1) of the plurality of plasma processingchambers is less than an upper limit and when all the loss capacitancesC_(X1) are less than 26 times the plasma electrode capacitance C_(e1)and that the plasma processing apparatus does not maintain the requiredlevel of performance when the variation is not less than the upper limitor when one of the loss capacitances C_(X1) is not less than 26 timesthe plasma electrode capacitance C_(e1), wherein the loss capacitanceC_(X1) is measured between the plasma excitation electrode and groundpotential positions which are DC-grounded.

According to another aspect of the present invention, in a performancemanagement system for a plasma processing apparatus which isdisassembled before transfer, is transported to a customer, and isreassembled at a customer site, the plasma processing apparatuscomprising: a plasma processing chamber including a plasma excitationelectrode for exciting a plasma; a radiofrequency feeder, the plasmaexcitation electrode being connected to the output end of theradiofrequency feeder; a radiofrequency generator for supplying aradiofrequency voltage to the plasma excitation electrode; and amatching circuit having an input terminal and an output terminal, theinput terminal being connected to the radiofrequency generator and theoutput terminal being connected to the input end of the radiofrequencyfeeder so as to achieve impedance matching between the plasma processingchamber and the radiofrequency generator, the performance managementsystem comprises a server; and a customer I/O device linked to theserver via a communication line, wherein the server receives a losscapacitance C_(X1) and a plasma electrode capacitance C_(e1) after thedelivery from the customer I/O device and transmits a signal indicatingthat a required level of performance is maintained when the losscapacitance C_(X1) is less than 26 times the plasma electrodecapacitance C_(e1) and a signal indicating that the required level ofperformance is not maintained when the loss capacitance C_(X1) is notless than 26 times the plasma electrode capacitance C_(e1) to thecustomer I/O device, wherein the loss capacitance C_(X1) is measuredbetween the plasma excitation electrode and ground potential positionswhich are DC-grounded and the plasma electrode capacitance C_(e1) ismeasured between the plasma excitation electrode and a counter electrodewhich generate a plasma in cooperation with each other.

According to another aspect of the present invention, in a performancemanagement system for a plasma processing apparatus which isdisassembled before transfer, is transported to a customer, and isreassembled at a customer site, the plasma processing apparatuscomprising: a plurality of plasma processing chambers including plasmaexcitation electrodes for exciting plasma; radiofrequency feeders, eachplasma excitation electrode being connected to the output end of thecorresponding radiofrequency feeder; at least one radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrodes; and at least one matching circuit having an inputterminal and an output terminal, the input terminal being connected tothe radiofrequency generator and the output terminal being connected tothe input end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chambers and the radiofrequencygenerator, the system comprises a server; and a customer I/O devicelinked to the server via a communication line, wherein the serverreceives a loss capacitance C_(X1) and a plasma electrode capacitanceC_(e1) after the delivery of each plasma processing chamber from thecustomer I/O device and transmits a signal indicating that a requiredlevel of performance is maintained when the loss capacitance C_(X1) isless than 26 times the plasma electrode capacitance C_(e1) and a signalindicating that the required level of performance is not maintained whenthe loss capacitance C_(X1) is not less than 26 times the plasmaelectrode capacitance C_(e1) to the customer I/O device, wherein theloss capacitance C_(X1) is measured between the plasma excitationelectrode and ground potential positions which are DC-grounded and theplasma electrode capacitance C_(e1) is measured between the plasmaexcitation electrode and a counter electrode which generate a plasma incooperation with each other.

According to another aspect of the present invention, in a performancemanagement system for a plasma processing apparatus which isdisassembled before transfer, is transported to a customer, and isreassembled at a customer site, the plasma processing apparatuscomprising: a plurality of plasma processing chambers including plasmaexcitation electrodes for exciting plasma; radiofrequency feeders, eachplasma excitation electrode being connected to the output end of thecorresponding radiofrequency feeder; at least one radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrodes; and at least one matching circuit having an inputterminal and an output terminal, the input terminal being connected tothe radiofrequency generator and the output terminal being connected tothe input end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chambers and the radiofrequencygenerator, the system comprises a server comprising an output device;and a customer I/O device linked to the server via a communication line,wherein the server receives data of identification numbers and plasmaelectrode capacitances C_(e1) of the plasma processing chambers afterthe delivery from the customer I/O device, and outputs theidentification numbers and a maintenance command through the outputdevice when a variation C_(e1r), defined by(C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)), between the maximumcapacitance C_(e1max) and the minimum capacitance C_(e1min) amongcapacitances C_(e1) is not less than an upper limit, wherein eachcapacitance C_(e1) is measured between the plasma excitation electrodeand a counter electrode which generate a plasma in cooperation with eachother, and wherein the server receives data of identification numbersand loss capacitances C_(X1) of the plasma processing chambers after thedelivery from the customer I/O device, and outputs the identificationnumbers and a maintenance command through the output device when avariation C_(X1r), defined by(C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between the maximumcapacitance C_(X1max) and the minimum capacitance C_(X1min) among losscapacitances C_(X1) is not less than an upper limit, wherein each losscapacitance C_(X1) is measured between the plasma excitation electrodeand ground potential positions which are DC-grounded.

According to another aspect of the present invention, in a performancemanagement system for a plasma processing system which is disassembledbefore transfer, is transported to a customer, and is reassembled at acustomer site, the plasma processing system comprising a plurality ofplasma processing apparatuses, each comprising: a plasma processingchamber including a plasma excitation electrode for exciting a plasma; aradiofrequency feeder, the plasma excitation electrode being connectedto the output end of the radiofrequency feeder; a radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrode; and a matching circuit having an input terminaland an output terminal, the input terminal being connected to theradiofrequency generator and the output terminal being connected to theinput end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chamber and the radiofrequencygenerator, the performance management system comprises a server; and acustomer I/O device linked to the server via a communication line,wherein the server receives a loss capacitance C_(X1) and a plasmaelectrode capacitance C_(e1) after the delivery from the customer I/Odevice and transmits a signal indicating that a required level ofperformance is maintained when the loss capacitance C_(X1) is less than26 times the plasma electrode capacitance C_(e1) and a signal indicatingthat the required level of performance is not maintained when the losscapacitance C_(X1) is not less than 26 times the plasma electrodecapacitance C_(e1) to the customer I/O device, wherein the losscapacitance C_(X1) is measured between the plasma excitation electrodeand ground potential positions which are DC-grounded and the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode and a counter electrode which generate a plasma in cooperationwith each other.

According to another aspect of the present invention, in a performancemanagement system for a plasma processing system which is disassembledbefore transfer, is transported to a customer, and is reassembled at acustomer site, the plasma processing system comprising a plurality ofplasma processing apparatuses, each comprising: a plasma processingchamber including a plasma excitation electrode for exciting a plasma; aradiofrequency feeder, the plasma excitation electrode being connectedto the output end of the radiofrequency feeder; a radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrode; and a matching circuit having an input terminaland an output terminal, the input terminal being connected to theradiofrequency generator and the output terminal being connected to theinput end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chamber and the radiofrequencygenerator, the performance management system comprises: a server; and acustomer I/O device linked to the server via a communication line,wherein the server receives data of identification numbers and plasmaelectrode capacitances C_(e1) of the plasma processing chambers afterthe delivery from the customer I/O device, and outputs theidentification numbers and a maintenance command through the outputdevice when a variation C_(e1r), defined by(C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)), between the maximumcapacitance C_(e1max) and the minimum capacitance C_(e1min) amongcapacitances C_(e1) is not less than an upper limit, wherein eachcapacitance C_(e1) is measured between the plasma excitation electrodeand a counter electrode which generate a plasma in cooperation with eachother; and

wherein the server receives data of identification numbers and losscapacitances C_(X1) of the plasma processing chambers after the deliveryfrom the customer I/O device, and outputs the identification numbers anda maintenance command through the output device when a variationC_(X1r), defined by (C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), betweenthe maximum capacitance C_(X1max) and the minimum capacitance C_(X1min)among loss capacitances C_(X1) is not less than an upper limit, whereineach loss capacitance C_(X1) is measured between the plasma excitationelectrode and ground potential positions which are DC-grounded.

According to another aspect of the present invention, a performancevalidation system for a plasma processing apparatus comprises a customerterminal, an engineer terminal, and information providing means, whereinthe customer terminal requests browsing of performance information tothe information providing means via a public line, the performanceinformation including the operational state of the plasma processingapparatus which is disassembled before transfer, is transported to acustomer, and is reassembled at a customer site and which is controlledby the above-mentioned performance management system, the performanceinformation is uploaded by a maintenance engineer to the informationproviding means through the engineer terminal, and the informationproviding means provides the performance information uploaded from theengineer terminal to the customer terminal upon the request from thecustomer terminal.

Preferably, in the above-aspects, both the upper limits for thevariation C_(e1r) and the variation C_(X1r) are 0.1. More preferably,both the upper limits for the variation C_(e1r) and the variationC_(X1r) are 0.03.

In the performance management system for a plasma processing apparatusaccording to one of the above aspects, the server preferably comprisesan output device at a delivery site, the output device outputting amaintenance command when the loss capacitance C_(X1) is not less than 26times the plasma electrode capacitance C_(e1) in any one of theplurality of the plasma processing chamber.

In the performance validation system according to one of the aboveaspects, the performance information preferably includes the plasmaelectrode capacitance C_(e) and the loss capacitance C_(X). Furthermore,the performance information may be output as a catalog orspecifications.

According to the performance evaluation method for a plasma processingapparatus or system of this invention, whether the plasma processingapparatus or system exhibits a required performance level can be readilyand rapidly inspected after the reassembly of the plasma processingapparatus previously disassembled for the purpose of transfer, afterperformance of plasma treatments, or after adjustment works such asoverhaul, parts replacement, and assembly with alignment.

According to a maintenance method for the plasma processing apparatus ofthis invention, a defective plasma processing apparatus can be readilyand rapidly corrected to the desired performance level.

According to the performance management system for the plasma processingapparatus or system of this invention, the plasma processing apparatuscan be managed to be at the required performance level from the deliverysite as well as the customer site. Thus, a manufacturer or a maintenancecompany can provide better maintenance service to customers.

Furthermore, the plasma processing apparatus of this invention can beeasily maintained to be at the required performance level so as tocontinuously perform satisfactory plasma processes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of the outline of the structure of aplasma processing apparatus according to the first embodiment;

FIG. 2 is a schematic view of a matching circuit of the plasmaprocessing apparatus shown in FIG. 1;

FIG. 3 is a cross-sectional view of the upper component of the plasmaprocessing apparatus shown in FIG. 1;

FIG. 4 is a schematic view explaining the loss capacitance C_(X) of theupper component of the plasma processing chamber shown in FIG. 3;

FIG. 5 is an equivalent circuit diagram illustrating the losscapacitance C_(X) of the upper component shown in FIG. 4;

FIG. 6 is an equivalent circuit diagram illustrating the impedancecharacteristics of the plasma processing chamber shown in FIG. 1;

FIG. 7 is a schematic view of the plasma processing chamber forexplaining the equivalent circuit diagram shown in FIG. 6;

FIG. 8 is a circuit diagram illustrating the relationship between asupplied current I_(˜), a plasma current I_(e), and a loss currentI_(x);

FIG. 9 is an isometric view of a probe of an impedance meter;

FIG. 10 is a schematic view showing a connection of the probe shown inFIG. 9;

FIG. 11 is a schematic view of a plasma processing apparatus inaccordance with a second embodiment of the present invention;

FIG. 12 is a cross-sectional view of the upper component of the plasmaprocessing apparatus shown in FIG. 11;

FIG. 13 is an equivalent circuit diagram of the plasma processingchamber shown in FIG. 11;

FIG. 14 is a schematic view of the state of the space between twoelectrodes when a plasma is generated;

FIG. 15 is a block diagram of a performance management system for aplasma processing apparatus in accordance with a third embodiment of thepresent invention;

FIG. 16 is a flowchart illustrating a method for providing evaluationinformation which is prepared by the performance management system shownin FIG. 15;

FIG. 17 is a block diagram of a performance management system for aplasma processing apparatus in accordance with a fourth embodiment ofthe present invention;

FIG. 18 is a flowchart illustrating a method for providing evaluationinformation which is prepared by the performance management system shownin FIG. 17;

FIG. 19 is a flowchart illustrating a method for providing evaluationinformation for a plasma processing apparatus in accordance with a fifthembodiment of the present invention;

FIG. 20 is a block diagram of a performance management system for aplasma processing apparatus in accordance with the present invention;

FIG. 21 is a flowchart illustrating processing for providing performanceinformation from a server in the performance validation system of theplasma processing apparatus in accordance with the present invention;

FIG. 22 shows an output form of a main page CP in accordance with theperformance validation system of the plasma processing apparatus of thepresent invention;

FIG. 23 shows an output form of a subpage CP1 in accordance with theperformance validation system of the plasma processing apparatus of thepresent invention;

FIG. 24 shows an output form of a subpage CP2 in accordance with theperformance validation system of the plasma processing apparatus of thepresent invention;

FIG. 25 shows an output form of a subpage CP3 in accordance with theperformance validation system of the plasma processing apparatus of thepresent invention;

FIG. 26 shows an output form of a subpage CP4 in accordance with theperformance validation system of the plasma processing apparatus of thepresent invention;

FIG. 27 is a schematic view of a plasma processing apparatus which isused in a performance evaluation method in accordance with a ninthembodiment of the present invention;

FIG. 28 is a cross-sectional view of a laser-annealing chamber shown inFIG. 27;

FIG. 29 is a cross-sectional view of an annealing chamber shown in FIG.27;

FIG. 30 is a schematic view of a plasma processing apparatus which isused in a performance evaluation method in accordance with a tenthembodiment of the present invention;

FIG. 31 is a schematic view of a plasma processing system which is usedin a performance evaluation method in accordance with an eleventhembodiment of the present invention;

FIG. 32 is a schematic view of a plasma processing apparatus which isused in a performance evaluation method in accordance with the presentinvention;

FIG. 33 is a schematic view of a plasma processing apparatus which isused in a performance evaluation method in accordance with the presentinvention;

FIG. 34 is a schematic view of a plasma processing apparatus which isused in a performance evaluation method in accordance with the presentinvention;

FIG. 35 is a block diagram of a performance management system for aplasma processing apparatus in accordance with a twelfth embodiment ofthe present invention;

FIG. 36 is a block diagram of a performance management system for aplasma processing apparatus in accordance with a thirteen embodiment ofthe present invention;

FIG. 37 is a flowchart illustrating a method for providing evaluationinformation which is prepared by the performance management system shownin FIG. 36;

FIG. 38 is a schematic cross-sectional view of a conventional plasmaprocessing apparatus; and

FIG. 39 is a schematic cross-sectional view of another conventionalplasma processing apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described in detail.

In the present invention, the loss capacitance C_(X) between the plasmaexcitation electrode connected to a radiofrequency generator and groundpotential positions which are DC-grounded is used as an evaluationparameter. The loss capacitance C_(X) has a close connection withperformance of the plasma processing apparatus, for example, effectivepower consumption in a plasma space and significantly varies bymisalignment in assembling or reassembling and contamination duringoperation of the apparatus. Furthermore, the loss capacitance C_(X)significantly varies by vibration during transportation.

The present inventors have found that the absolute value of thedifference ΔC_(X) between a loss capacitance C_(X1) at a later time t1and a loss capacitance C_(X0) at a time t₀ has a close connection withthe variation in the performance of the plasma processing apparatus andthat this variation falls within a certain range when the absolute valueis less than a certain value. Thus, the plasma processing apparatus canbe evaluated by comparing the absolute value of the difference ΔC_(X)with the certain value.

Accordingly, the comparison of the absolute value of the differenceΔC_(X) with the certain value can evaluate whether or not the plasmaprocessing chamber maintains a required level of performance ininstallation, use, and overhauling and inspection of the plasmaprocessing apparatus and whether or not a plurality of plasma processingchambers in the plasma processing apparatus has a small difference inperformance.

Since the loss capacitance C_(X) can be readily measured, the evaluationcan be achieved with a significantly reduced measurement time comparedwith conventional inspection methods by actual deposition ontosubstrates. Moreover, this measurement method has high productivity withreduced expenses for substrates used in the inspection, processing ofthese substrates, and labor during the inspection operations.

Accordingly, the performance evaluation method in accordance with thepresent invention can rapidly evaluate the performance of a plasmaprocessing apparatus with reduced cost. When the plasma processingapparatus includes a plurality of plasma processing chambers, the samelayer deposition is achieved using the same process recipe in theseplasma processing chambers under the control of the loss capacitanceC_(X). When layers are continuously formed in these plasma processingchambers, these layers can have substantially the same characteristics,e.g., the thickness, the isolation voltage, and the etching rate.

Moreover, this performance evaluation method does not require a largeevaluation cost; hence, the performance evaluation can be performed at arequired time and the results can be immediately fed back to acorrective action.

The performance evaluation method in accordance with the presentinvention can also rapidly evaluate the performance of a plasmaprocessing system with reduced cost. Since the plasma processing systemincludes a plurality of plasma processing chambers, the same layerdeposition is achieved using the same process recipe in these plasmaprocessing chambers under the control of the loss capacitance C_(X).When layers are continuously formed in these plasma processing chambers,these layers can have substantially the same characteristics, e.g., thethickness, the isolation voltage, and the etching rate.

According to the performance management system for the plasma processingapparatus or system of the present invention, customers can readilyobtain the results of the performance evaluation from a server which iscontrolled by the manufacturer. Moreover, the customers can readilyobtain the information about differences in characteristics betweenplasma processing chambers of the plasma processing system.

Since the plasma processing apparatus is maintained at a satisfactorylevel by the loss capacitance C_(X) which can be easily measured at anytime, the plasma treatment will be satisfactorily achieved.

According to the performance validation system for the plasma processingapparatus of the present invention, customers can obtain the operationalstatuses of their own plasma processing apparatuses from a servercontrolled by a maintenance engineer.

Thus, in the present invention, the plasma processing apparatus can bemaintained at a satisfactory level by a corrective action which isperformed before the plasma processing apparatus yields problematicresults.

Moreover, substantially the same results can always be obtained by thesame process recipe for the plasma processing chamber. When layers arecontinuously deposited in the processing chamber, these layers will havesubstantially the same characteristics, e.g., the thickness, theisolation voltage, and the etching rate.

When the plasma processing apparatus or system includes a plurality ofplasma processing chambers, each plasma processing chamber can becontrolled using the loss capacitance C_(X) thereof.

In the present invention, the loss capacitance C_(X) is set such thatthe loss capacitance C_(X) is less than 26 times the plasma electrodecapacitance C_(e) between two electrodes. Since the shunt component ofthe current from the radiofrequency generator is reduced, the inputpower can be effectively consumed in the plasma chamber. Thus, theeffective power consumption in the plasma space is achieved comparedwith conventional plasma processing apparatuses when the same frequencyis supplied. In a layer deposition process, the deposition rate will beimproved.

Supposing the imaginary unit being j (j²=−1) and the angular frequencybeing ω(ω=2πf_(e) wherein f_(e) is a power frequency), the impedance Z(Ω) is represented by relationship (11):Z∝−j/ωC  (11)wherein C is the capacitance. Thus, the impedance can be determined bydefining the capacitance. Since the current I is in inverse proportionto the impedance Z (Ω), the plasma current I_(e) flowing in the plasmaspace can be increased due to an increased impedance for the groundpotential positions when a radiofrequency power of 13.56 MHz or more isused.

Since the loss capacitance C_(X) is radiofrequency characteristicsmainly depending on the mechanical structure, the individual plasmaprocessing chambers have different values. By controlling the losscapacitance C_(X) to the above-described conditions, the overallradiofrequency characteristics of the plasma processing chambers can beoptimized, achieving stable plasma generation. As a result, an increasein the loss current I_(x) relative to the plasma current I_(e) can besuppressed, preventing power consumption loss and decreased plasmadensity in the plasma space.

Accordingly, the loss capacitance C_(X) is useful as a parameter forevaluating the stability of the plasma generated in the plasma space andthe uniformity of the operation.

Preferably, the loss capacitance C_(X) is set such that the losscapacitance C_(X) is less than 7 times the plasma electrode capacitanceC_(e) in the present invention. Since the shunt component of the currentto the ground potential positions is further reduced, the input powercan be more effectively consumed in the plasma chamber, resulting in animproved processing rate. In the layer deposition process, layers havingimproved characteristics can be formed at improved deposition rates. Forexample, an insulating layer deposited in the present invention exhibitsa high isolation voltage. Since the radiofrequency current isconcentrated between the two electrodes, the radiofrequency power ismore effectively consumed in the plasma space. Thus, the resulting layerhas planar uniformity, namely, reduced variations in thickness andisolation voltage in the planar direction.

More preferably, the loss capacitance C_(X) is set such that the losscapacitance C_(X) is less than 5 times the plasma electrode capacitanceC_(e) in the present invention. Since the shunt component of the currentto the ground potential positions is further reduced, the input powercan be more effectively consumed in the plasma chamber, resulting inreduced power consumption and operational cost. In the layer depositionprocess, layers having improved characteristics can be formed atimproved deposition rates. In the layer deposition, the resulting layerhas planar uniformity, namely, reduced variations in thickness andisolation voltage in the planar direction.

The loss capacitance C_(X) will now be described.

As shown in FIG. 8, the current I_(˜) supplied from a radiofrequencygenerator is divided into a plasma current I_(e) which flows in a plasmaspace formed between the parallel plate electrodes constituting theplasma electrode capacitance C_(e) and a loss current I_(x) which is ashunt component flowing into the other portions. In other words, theloss capacitance C_(X) is the sum of the capacitance components whichare generated between the plasma excitation electrode connected to theradiofrequency generator and the ground potential positions and does notinclude the plasma electrode capacitance C_(e).

The range for measuring the loss capacitance C_(X) will now bedescribed.

As shown in FIG. 1, the plasma electrode capacitance C_(e) is measuredbetween parallel plate electrodes 4 and 8, and the loss capacitanceC_(X) of the plasma processing chamber 95 means that of an uppercomponent 19 which is measured at the output terminal position PR.

FIG. 2 shows a matching circuit 2A. A coil 23 and a tuning capacitor 24are arranged in series between a radiofrequency generator 1 and a plasmaexcitation electrode 4, and a load capacitor 22 is arranged in parallelto the radiofrequency generator 1. The other end of the matching circuit2A is grounded. When the loss capacitance C_(X) of the plasma processingchamber is measured, the matching circuit 2A is disconnected from theplasma excitation electrode 4 at a position PR which corresponds to theoutput terminal of the tuning capacitor 24.

FIG. 4 is a schematic view of an upper component when the losscapacitance C_(X) is measured.

When the entire capacitance of the upper component is measured, theupper component is detached from the plasma processing chamber and thecapacitance component of the plasma excitation electrode 4 is measuredat the output terminal position PR to determine the loss capacitanceC_(X). The loss capacitance C_(X) is the sum of the capacitances C_(A),C_(B), and C_(C) as shown in FIG. 5.

Instead of the above-described measuring point, as shown in FIG. 1, ameasuring point PR2 which corresponds to the input end of theradiofrequency feed line may be employed to define the measuring region.In this case, the measuring range includes a radiofrequency feed line,the matching circuit, the radiofrequency feed plate, and the plasmaexcitation electrode side of the plasma processing chamber.

Instead of the above-described measuring point, as shown in FIG. 1, ameasuring point PR3 which corresponds to the input terminal of thematching circuit 2A connected to the feed line 1A may be employed todefine the measuring region of the plasma processing chamber. In thiscase, the measuring region includes the matching circuit, theradiofrequency feed plate, and the plasma excitation electrode side ofthe plasma processing chamber.

In the present invention, the absolute value of the difference ΔC_(X)between the loss capacitance C_(X0) at the time t₀ and the losscapacitance C_(X1) at the later time t1 is less than an upper limit. Theupper limit is not limited in the present invention and is preferably10% of the loss capacitance C_(X0). In such a case, a plasma enhancedCVD apparatus has a variation in deposition rate of ±5% or less and avariation in layer characteristics of ±5% in the planar direction of thelayer, wherein the layer characteristics include the layer thickness andthe isolation voltage.

More preferably, the upper limit is ±3% of the loss capacitance C_(X0).In such a case, a plasma enhanced CVD apparatus has a variation indeposition rate of ±2% or less and a variation in layer characteristicsof ±2% in the planar direction of the layer, wherein the layercharacteristics include the layer thickness and the isolation voltage.

In the present invention, an evaluation standard (Evaluation Standard 1)is whether or not the loss capacitance C_(X1) after the delivery is lessthan 26 times the plasma electrode capacitance C_(e1).

When the loss capacitance C_(X1) is less than 26 times the plasmaelectrode capacitance C_(e1), the shunt component other than a currentflowing between the electrodes can be reduced, thus effectivelyintroducing radiofrequency power into the plasma space. When the samefrequency is supplied, the plasma processing apparatus of the presentinvention more effectively consumes the electrical power in the plasmaspace than conventional apparatuses. In a layer deposition process, thedeposition rate is increased.

As described above, the loss capacitance C_(X) are radiofrequencycharacteristics mainly depending on the mechanical structure; hence, theindividual plasma processing chambers have different values. Byevaluating the performance based on the loss capacitance C_(X), theoverall radiofrequency characteristics of the plasma processing chamberscan be optimized, achieving stable plasma generation. Thus, theperformance evaluation method and the performance management system canmaintain high operational stability of the plasma processing apparatus.Such a performance evaluation method has not been considered inconventional processes.

In the present invention, another evaluation standard (EvaluationStandard 2) is whether or not the variation C_(e1r) between the plasmaelectrode capacitances C_(e1) after delivery is less than the upperlimit and whether or not the variation C_(X1r) between the losscapacitances C_(X1) after delivery is less than the upper limit.

The plasma electrode capacitance C_(e1) is measured for each of aplurality of plasma processing chambers to determine the maximumC_(e1max) and the minimum C_(e1min). The variation C_(e1r) is defined bythe following equation:C _(e1r)=(C _(e1max) −C _(e1min))/(C _(e1max) +C _(e1min))

When the variation C_(e1r) is less than the upper limit, these plasmachambers have substantially the same radiofrequency characteristics suchas the plasma electrode capacitance C_(e). Since these plasma processingchambers can be controlled within a predetermined range, these chambersconsume substantially the same electrical power in the plasma spacesthereof.

The loss capacitance C_(X) is also measured for each of a plurality ofplasma processing chambers to determine the maximum C_(X1max) and theminimum C_(X1min). The variation C_(X1r) is defined by the followingequation:C _(X1r)=(C _(X1max) −C _(X1min))/(C _(X1max) +C _(X1min))

When the variation C_(X1r) is less than the upper limit, these plasmachambers have substantially the same radiofrequency characteristics suchas the plasma electrode capacitance C_(X). Since these plasma processingchambers can be controlled within a predetermined range, these chambersconsume substantially the same electrical power in the plasma spacesthereof.

As a result, substantially the same results can be obtained by the sameprocess recipe for these plasma processing chambers. When layers aredeposited in these processing chambers, these layers will havesubstantially the same characteristics, e.g., the thickness, theisolation voltage, and the etching rate.

In the present invention, Standard Evaluations 1 and 2 may be used incombination. In this case, the performance evaluation method allows theplasma processing apparatus to maintain at a highly stable operationstate. Moreover, the performance evaluation method maintains reduceddifferences in radiofrequency characteristics such as the plasmaelectrode capacitance C_(e) and the loss capacitance C_(X) between thedifferent plasma processing chambers.

In this case, the upper limit of the variation C_(e1r) in the plasmaelectrode capacitances C_(e1) after the delivery may be any value, forexample, 0.1. Also, the upper limit of the variation C_(X1r) in the losscapacitances C_(X1) after the delivery may be any value, for example,0.1. When the upper limit is 0.1, the variation in layer thickness canbe controlled within ±5%, resulting in uniform plasma deposition.

When the upper limit is 0.03, the different plasma processing chambershave substantially the same radiofrequency characteristics such as theplasma electrode capacitance C_(e) and the loss capacitance C_(X). Theseplasma processing chambers can be controlled within a predeterminedlevel using the impedance characteristics, consuming substantially thesame power in the plasma spaces thereof.

As a result, substantially the same results can be obtained by the sameprocess recipe for these plasma processing chambers. When layers areformed in these processing chambers, these layers can have substantiallythe same characteristics, e.g., the thickness, the isolation voltage,and the etching rate. When the upper limit is 0.03, the variation inlayer thickness can be controlled within ±2%, resulting in uniformplasma deposition.

The performance management system for the plasma processing apparatus orsystem of the present invention evaluates whether or not the plasmaprocessing apparatus or system is maintained at a time t₀ after theapparatus or system is disassembled at the delivery site, transferred tothe customer site, and reassembled and used at the customer site and ata later time t1 in use in order to control the performance of theapparatus or system.

A server used in this system is controlled by a delivery site, forexample, a manufacturer, a distributor, or a maintenance engineer. Theserver may be placed at any site. The server stores the loss capacitanceC_(X0) before disassembly of the loss capacitance C_(X). Using the losscapacitance C_(X), the performance of the plasma processing apparatus atthe customer site is evaluated. Preferably, the server also stores theplasma electrode capacitance C_(e0) before disassembly of the plasmaelectrode capacitance C_(e). In such a case, the performance of theplasma processing apparatus at the customer site is evaluated using theplasma electrode capacitance C_(e0).

The loss capacitance C_(X0) may be a standard loss capacitance C_(X)which is controlled by the manufacturer. Alternatively, the losscapacitance C_(X0) and the plasma electrode capacitance C_(e0) may bestored for the identification number of each plasma processing chamberto more precisely evaluate each plasma processing chamber at thecustomer site. In such a case, the performance management system becomesmore precise.

The identification number of the plasma processing chamber may be of anyform and may include numerals and characters. In a plasma processingapparatus having one plasma processing chamber, the serial number of theplasma processing apparatus may be used as the identification number ofthe plasma processing chamber.

The server is linked to an I/O device installed at the customer site viaa communication line. The communication line may be of any form whichcan perform transmitting/receiving of signals between the server and theI/O device which are distant from each other. Examples of communicationlines are communication media, such as cables, optical fiber lines,satellite circuits, telephone lines, and the Internet. The I/O deviceslocated at the customer site are also not limited and are selected frompersonal computers, dedicated terminals, telephones, etc. according tothe type of the communication line used. In the performance managementsystem using Evaluation Standard 2, the I/O device at the delivery sitemust have an input function and may have an output function.

The server receives data of the loss capacitance C_(X1) and the plasmaelectrode capacitance C_(e1) after the delivery or reassembly from thecustomer I/O device. The server may receive the identification number ofthe corresponding plasma processing apparatus or chamber, if necessary.Herein, “after the delivery” includes “immediately after reassembly” and“in use” after the reassembly. Accordingly, the server can continuallyreceives data of the loss capacitance C_(X1) and the plasma electrodecapacitance C_(e1) which reflect the performance of the plasmaprocessing apparatus or system at the customer site anytime. In theperformance management system using Evaluation Standard 1, the serverstores data of the plasma electrode capacitance C_(e) (particularly, theplasma electrode capacitance C_(e0)) and the loss capacitance C_(X)(particularly, the loss capacitance C_(X0)) which evaluate theperformance of the plasma processing apparatus at the customer site. Theserver may receive data of the loss capacitance C_(X1) after thedelivery and the plasma electrode capacitance C_(e1) after the deliveryof the plasma electrode capacitance C_(e1) together with theidentification number of the plasma processing apparatus or chamber fromthe I/O device at the delivery site, if necessary.

In the transmission of values of the loss capacitance C_(X1), the plasmaelectrode capacitance C_(e1), and the identification number of theplasma processing apparatus or chamber to the server, the user or amaintenance engineer may manually input these values through thecustomer I/O device. The input operation can be automated or simplified.For example, a meter for measuring the capacitance is connected to boththe plasma processing apparatus or chamber and the customer I/O deviceto directly transmit the data of the loss capacitance C_(X1) and thelike to the server. In the case of a plasma processing apparatus havinga single plasma processing chamber, the identification number of theplasma processing chamber is preliminarily stored in the customer I/Odevice and no input operation for the identification number is requiredfor subsequent procedures.

The server calculates the absolute value of the difference ΔC_(X) usingthe loss capacitance C_(X0) and the plasma electrode capacitance C_(e0)in the internal arithmetic processing unit. The server transmits to theI/O device at the customer a signal indicating that a required level ofperformance is maintained when the absolute value is less than the upperlimit and a signal indicating that the required level of performance isnot maintained when the absolute value is not less than the upper limit.Moreover, the server compares the loss capacitance C_(X1) after thedelivery with the plasma electrode capacitance C_(e1) in the internalarithmetic processing unit and transmits to the I/O device at thecustomer site a signal indicating that the required level of performanceis maintained when the loss capacitance C_(X1) is less than 26 times theplasma electrode capacitance C_(e1) and a signal indicating that therequired level of performance is not maintained when the losscapacitance C_(X1) is not less than 26 times the plasma electrodecapacitance C_(e1). Thus, the performance of the plasma processingapparatus or chamber can be evaluated at the customer site based on theevaluation information transmitted from the server. The customer I/Odevice outputs the results of the performance evaluation in any form,for example, display, print, or alarm signal.

The server is preferably provided with an output device at the deliverysite to output a maintenance command therefrom when the absolute valueof the difference ΔC_(X) is not less than the upper limit. In this case,the identification number of the corresponding plasma processing chamberis preferably output so as to rapidly detect the defect of thecorresponding plasma processing chamber at the delivery site and topromptly start maintenance services. The output device provided to theserver may output a maintenance command when the loss capacitance C_(X1)is not less than 26 times the plasma electrode capacitance C_(e1).

If the server is not located at the delivery site, the server and theoutput device may be linked via any communication line.

In the case of providing the evaluation information from the server toboth the output device at the customer site and the output device at thedelivery site, the upper limits for these two output devices are notnecessarily the same. For example, an upper limit of 10% for the losscapacitance C_(X) is set to the I/O device at the customer site and asignal indicating that the required level of the performance is notmaintained when the loss capacitance C_(X1) is not less than the upperlimit. On the other hand, an upper limit of 3% for the loss capacitanceC_(X) is set to the output device at the delivery site and a maintenancecommand is output when the loss capacitance C_(X1) is not less than theupper limit of 3%. Since the maintenance command is output to the outputdevice at the delivery site based on the severer evaluation standard, amaintenance engineer can provide maintenance service before theperformance of the plasma processing apparatus significantly varies,namely, preventive service.

The performance management system for the plasma processing apparatusaccording to another embodiment of the present invention also evaluateswhether or not the plasma processing apparatus maintains a requiredlevel of performance at a later time t1 after a time t₀ when theapparatus is reassembled at a customer site or used at the customersite.

In this performance management system, the server stores maintenanceengineer information which includes performance levels, such as faultlevels, which correspond to predetermined ranges, and maintenanceengineer's names which are registered in response to the fault levels.Moreover, the server has an output device at the delivery site. When theabsolute value of the difference ΔC_(X) falls within one of the faultlevels, the server outputs a maintenance command with the information onthe service engineer which is registered according to the fault level.

This performance management system outputs the fault level and theinformation of a service engineer having a skill which is suitable forthe fault level, in addition to a maintenance command at the deliverysite

Thus, the fault level of the plasma processing apparatus placed at thecustomer site can be readily evaluated at the delivery site according tothis performance management system. A maintenance engineer having skillwhich is suitable for the fault level is thereby sent to the customersite, thus providing rapid and adequate maintenance services with anefficient engineer distribution. Accordingly, the maintenance systemafter installation becomes rationalized.

In the performance management system using Evaluation Standard 2, theserver has an output device. The output device may be placed anywhere,and preferably is placed at a site which provides maintenance services,for example, the delivery site, the manufacturer site, or a maintenancecenter. If the server is distant from the output device, these may belinked via any communication line.

The server evaluates the performance of the plasma processing apparatusat the customer site by Standard Evaluation 2 and outputs a maintenancecommand and the identification numbers of the plasma processing chambershaving the maximum C_(e1max), minimum C_(e1min), the maximum C_(e1max),and minimum C_(e1min) when the results are not desirable.

The server receives data of the loss capacitance C_(X1) and the plasmaelectrode capacitance C_(e1) after the deliver from the customer I/Odevice before the evaluation based on Evaluation Standard 2. Herein,“after the delivery” includes “immediately after reassembly” and “inuse” after the reassembly. Accordingly, the server can continuallyreceives data of the plasma electrode capacitance C_(e1) and the losscapacitance C_(X1) which reflect the performance of the plasmaprocessing apparatus or system at the customer site anytime.

The server also receives the identification numbers of the plasmaprocessing chambers having the plasma electrode capacitance C_(e1) andthe loss capacitance C_(X1).

The server receives data of the loss capacitances C_(X1) of all plasmaprocessing chambers included in the plasma processing apparatus orsystem and specifies the maximum C_(X1max), the minimum C_(X1min), andthe identification numbers of the plasma processing chambers having themaximum or minimum. Next, the server calculates the variation C_(X1r)according to the equation:C _(X1r)=(C _(X1max) −C _(X1min))/(C _(X1max) +C _(X1min))When the variation C_(X1r) is not less than the upper limit, the outputdevice outputs a maintenance command and the identification numbers ofthe plasma processing chambers having the maximum C_(X1max) or minimumC_(X1min).

Also, the server receives data of the plasma electrode capacitancesC_(e1) of all plasma processing chambers included in the plasmaprocessing apparatus or system and specifies the maximum C_(e1max), theminimum C_(e1min), and the identification numbers of the plasmaprocessing chambers having the maximum or minimum. Next, the servercalculates the variation C_(e1r) according to the equation:C _(e1r)=(C _(e1max) −C _(e1min))/(C _(e1max) +C _(e1min))When the variation C_(e1r) is not less than the upper limit, the outputdevice outputs a maintenance command and the identification numbers ofthe plasma processing chambers having the maximum C_(e1max) or minimumC_(e1min).

The defect of the plasma processing apparatus or system at the customersite can be rapidly detected at the maintenance engineer site, promptingmaintenance services.

In the performance validation system for the plasma processing apparatusin accordance with the present invention, the customer can view theperformance information which represents the operation performance ofthe plasma processing chambers uploaded by the maintenance engineer onan information terminal via a public line. In other words, themaintenance engineer rapidly provides the operation performance andmaintenance information of the plasma processing apparatus in use to thecustomer. Since the performance information includes data of the losscapacitance C_(X) and the plasma electrode capacitance C_(e), thecustomer can evaluate the performance of the plasma processingapparatus. The performance information may be output as a catalog orspecifications.

First Embodiment

A plasma processing apparatus according to a first embodiment of thepresent invention will now be described with reference to the drawings.

FIG. 1 is a cross-sectional view showing the general structure of aplasma processing apparatus 75 according to the first embodiment. FIG. 2illustrates a matching circuit 2A of the plasma processing apparatus 75shown in FIG. 1. FIG. 3 is a cross-sectional view of an upper componentof the plasma processing apparatus 75 shown in FIG. 1.

The plasma processing apparatus 75 of this embodiment is of asingle-frequency excitation type and performs plasma processing such asplasma-enhanced chemical vapor deposition (CVD), dry etching, ashing,and the like. Referring to FIG. 1, the plasma processing apparatus 75comprises a plasma processing chamber 60 having parallel plateelectrodes 4 and 8, namely, a plasma excitation electrode (cathode) 4for exciting a plasma and a susceptor electrode (counter electrode) 8, aradiofrequency generator 1 connected to the plasma excitation electrode4, and a matching circuit 2A for matching the impedance between theplasma processing chamber 60 and the radiofrequency generator 1.

In this plasma processing apparatus 75, 26 times the plasma electrodecapacitance C_(e) between the parallel plate electrodes 4 and 8 islarger than the loss capacitance C_(X) between the plasma excitationelectrode 4 and ground potential positions which are DC-grounded. Theabsolute value of the difference ΔC_(X) between a loss capacitanceC_(X0) measured at a time t₀ and a loss capacitance C_(X1) measured at alater time t₁ after reassembly of the plasma processing apparatus oncedisassembled for the purpose of transfer or during the subsequent periodof use is maintained at a value less than 10% of C_(X0).

The plasma processing apparatus 75 of this embodiment will now bedescribed in greater detail. As shown in FIGS. 1 to 3, a shower plate 5and the plasma excitation electrode 4 connected to the radiofrequencygenerator 1 are arranged on the plasma processing chamber 60. Thesusceptor electrode 8 for receiving a substrate 16 opposes the showerplate 5 in the plasma processing chamber 60. The plasma excitationelectrode 4 is connected to the radiofrequency generator 1 via a feedplate (radiofrequency feeder) 3, the matching circuit 2A, and a feedline (radiofrequency supplier) 1A. The plasma excitation electrode 4 andthe feed plate 3 are covered by a chassis 21, and the matching circuit2A is housed inside a matching box 2 made of a conductor.

A silver-plated copper plate 50 to 100 mm in width, 0.5 mm in thickness,and 100 to 300 mm in length may be used as the feed plate 3, forexample. The input end of the feed plate 3 is screwed to the outputterminal of the matching circuit 2A, and the output end of the feedplate 3 is screwed to the plasma excitation electrode 4.

The plasma excitation electrode 4 has a projection 4 a at the bottomface thereof. The shower plate 5 having many holes 7 is provided underthe plasma excitation electrode 4 contacting the projection 4 a. Theplasma excitation electrode 4 and the shower plate 5 define a space 6. Agas feeding tube 17 is connected to the space 6.

The gas feeding tube 17 is connected to the space 6. The gas feedingtube 17 is composed of a conductor, and is provided with an insulator 17a in a midway thereof to insulate between the plasma excitationelectrode 4 and the gas supply source.

The gas fed from the gas feeding tube 17 flows into a plasma processingchamber 60 comprising a chamber wall 10 via the holes 7 of the showerplate 5. The chamber wall 10 and the plasma excitation electrode(cathode) 4 are isolated from each other by an insulator 9. The exhaustsystem is omitted from the drawing.

The susceptor electrode (wafer susceptor) 8 of a plate type whichreceives the substrate 16 and functions as another plasma excitationelectrode is provided in the plasma processing chamber 60.

An upper chamber wall 10 a is provided on the entire top of the chamberwall 10 and is separable from the chamber wall 10. A sealing means suchas an O-ring (not shown in the drawing) is provided between the upperchamber wall 10 a and the chamber wall 10 to secure hermetic sealingtherebetween. The upper chamber wall 10 a is integrated with the bottomof the side wall of the chassis 21, thus the upper chamber wall 10 a andthe chassis 21 having the same DC potential.

Referring to FIG. 3, the upper chamber wall 10 a, the plasma excitationelectrode 4, the shower plate 5, the insulator 9, the chassis 21, andthe gas feeding tube 17 constitute the upper component 19. The uppercomponent 19 is separable from the lower structure including the chamberwall 10, the susceptor electrode 8 and the like. The upper component 19can turn on a stator such as a hinge (not shown in the drawing) providedon the chamber wall 10 to open the plasma processing chamber 60.

The susceptor electrode 8 is connected to a shaft 13 extending through achamber bottom 10A at the center of the bottom face. The bottom endportion of the shaft 13 and the central portion of the chamber bottom10A are hermetically sealed by a bellows 11. The susceptor electrode 8and the shaft 13 are vertically movable by the bellows 11 to adjust thedistance between the plasma excitation electrode 4 and the susceptorelectrode 8.

The susceptor electrode 8 is connected to the shaft 13, and the shaft 13is connected to the bellows 11 which is connected to the chamber wall10. Thus, the susceptor electrode 8, the shaft 13, the bellows 11, thechamber bottom 10A, the chamber wall 10, and the upper chamber wall 10 ahave the same DC potential. Because the chamber wall 10, the upperchamber wall 10 a, and the chassis 21 are connected to each other, thechamber wall 10, the upper chamber wall 10 a, the chassis 21, and thematching circuit 2A have the same DC potential.

Herein, the matching circuit 2A is provided with a plurality of passiveelements in many cases in order to adjust the impedance of the plasmaprocessing chamber 60 in response to a change in the state of theplasma.

Referring to FIGS. 1 and 2, the matching circuit 2A has passiveelements, namely, a coil 23 and a tuning capacitor 24 connected inseries between the radiofrequency generator 1 and the feed plate 3, anda load capacitor 22 connected in parallel with the coil 23 and thetuning capacitor 24. One end of the load capacitor 22 is coupled to thematching box 2. The tuning capacitor 24 is connected to the plasmaexcitation electrode 4 via the feed plate 3.

The matching box 2 is connected to a shielding line of a feed line 1A ofa coaxial cable, and the shielding line is DC-grounded. Thus, thesusceptor electrode 8, the shaft 13, the bellows 11, the chamber bottom10A, the chamber wall 10, the chassis 21, and the matching box 2 are setto a ground potential. Also, one end of the load capacitor 22 isgrounded.

The plasma electrode capacitance C_(e) and the loss capacitance C_(X) inthe plasma processing apparatus 75 of this embodiment will now bedescribed. FIG. 4 is a schematic view explaining the loss capacitanceC_(X) of the upper component of the plasma processing apparatus 75, andFIG. 5 is an equivalent circuit diagram of the upper component shown inFIG. 4.

The plasma electrode capacitance C_(e) is a capacitance between theparallel plate electrodes 4 and 8, namely, the plasma excitationelectrode 4 and the susceptor electrode 8, and is defined by the areasof and the distance between these electrodes 4 and 8.

The loss capacitance C_(X) is the sum of the capacitance components forcurrents which flow in regions other than the path from the plasmaexcitation electrode 4 to the susceptor electrode 8. That is, the losscapacitance C_(X) is the sum of the capacitance components between theplasma excitation electrode 4 and individual ground potential positionswhich are DC grounded. Herein, the ground potential positions representall elements of the plasma processing apparatus 75 at the groundpotential except the susceptor electrode 8. That is, the groundpotential positions include the shaft 13, the bellows 11, the chamberbottom 10A, the chamber wall 10, the upper chamber wall 10 a, thechassis 21, the matching box 2, and the gas feeding tube 17. Indetermining the loss capacitance C_(X), only the gas feeding tube 17,the chassis 21, the upper chamber wall 10 a opposing the plasmaexcitation electrode 4 are considered as the ground potential positions,as shown in FIG. 4.

The loss capacitance C_(X) is defined as the sum of the capacitanceC_(A) between the plasma excitation electrode 4 and the gas feeding tube17 across the insulator 17 a, the capacitance C_(B) between the plasmaexcitation electrode 4 and the chassis 21, and the capacitance C_(C)between the plasma excitation electrode 4 and the upper chamber wall 10a.

In other words, as shown in FIG. 4, the loss capacitance C_(X) can beregarded equal to the sum of the capacitance components for theelectrical currents flowing from the plasma excitation electrode 4 intothe regions other than the susceptor electrode 8 in the upper component19 electrically separated from the plasma processing chamber 60.

In practice, as shown in FIG. 3, the loss capacitance C_(X) of the uppercomponent 19 separated from the chamber wall 10 (a separated state) ismeasured at a point PR corresponding to the output terminal of thematching circuit 2A. Herein, the separated state represents the state inwhich the plasma processing chamber 60 is opened by rotating the uppercomponent 19 on a hinge or the like. In the separated state, the uppercomponent 19 is physically separated from the chamber wall 10, and thecapacitance between the plasma excitation electrode 4 and the susceptorelectrode 8 is not measurable.

In measuring the loss capacitance C_(X) of the upper component 19 inthis embodiment, the matching circuit 2A is first separated from theupper component 19 at the output terminal of the passive element locatedat the last stage of the matching circuit 2A. As shown in FIG. 4, thematching circuit 2A is separated from the upper component 19 at theoutput the point PR of corresponding to the output terminal of thetuning capacitor by removing the screws connecting the feed plate 3 andthe matching circuit 2A to measure the loss capacitance C_(X) of theupper component 19.

Next, as shown by broken lines in FIG. 4, a probe 105 of an RFcharacteristic meter AN is connected to the point PR and a groundedposition, for example, the chassis 21 of the upper component 19. Theprobe 105 includes a lead wire 110, an insulating sheath 112 shieldingthe lead wire 110, and an outer conductor 111 covering the insulatingsheath 112, as shown in FIG. 4. The probe 105 is connected to the RFcharacteristic meter (impedance meter) AN via a coaxial cable. The leadwire 110 of the probe 105 is connected to the point PR, and the outerconductor 111 is connected to the grounded position in the upper centerof the chassis 21. The RF characteristic meter may be an LCR metermeasured at a fixed frequency or a tester provided with a capacitancemeasuring unit.

Referring to FIG. 5, the following radiofrequency components are therebymeasured as the loss capacitance C_(X):

The capacitance C_(A) between the plasma excitation electrode 4 and thegas feeding tube 17 separated by the insulator 17 a;

The capacitance C_(B) between the plasma excitation electrode 4 and thechassis 21; and

The capacitance C_(C) between the plasma excitation electrode 4 and theupper chamber wall 10 a.

In the plasma processing apparatus 75 of this embodiment, the plasmaelectrode capacitance C_(e) and the loss capacitance C_(X) are set suchthat 26 times the plasma electrode capacitance C_(e) is larger than theloss capacitance C_(X).

The plasma electrode capacitance C_(e) and the loss capacitance C_(X)can be adjusted to satisfy the above relationship, for example, asfollows:

(1) Adjusting the distance between and the areas of the plasmaexcitation electrode 4 and the susceptor electrode 8;

(2) Adjusting the overlapping area of the plasma excitation electrode 4and the upper chamber wall 10 a;

(3) Adjusting the material characteristics of the plasma excitationelectrode 4 and the upper chamber wall 10 a;

(4) Adjusting the thickness of the insulator provided between the plasmaexcitation electrode 4 and the upper chamber wall 10 a;

(5) Adjusting the distance between and the areas of the plasmaexcitation electrode 4 and the chassis 21;

(6) Adjusting the material characteristics of the insulator 17 a in thegas feeding tube 17; and

(7) Adjusting the length of the insulator 17 a.

In generating a plasma using the plasma processing apparatus 75 of thisembodiment, the upper component 19 is connected to the chamber wall 10;and the matching circuit 2A, the matching box 2, the radiofrequencypower feed line 1A, and the radiofrequency generator 1 are arranged atpredetermined positions. A power of 13.56 MHz or more, for example,13.56 MHz, 27.12 MHz, or 40.68 MHz is supplied from the radiofrequencygenerator 1 to generate a plasma between the parallel plate electrodes 4and 8. Using the plasma, a plasma treatment, such as a chemical vapordeposition (CVD) treatment, a sputtering treatment, a dry etchingtreatment, or an ashing treatment, is performed on the substrate 16placed on the susceptor electrode 8.

The radiofrequency current supplied from the radiofrequency generator 1flows through the coaxial cable of the radiofrequency power feed line1A, the matching circuit 2A, the feed plate 3, and the plasma excitationelectrode 4. The radiofrequency current further flows through the plasmaprocessing chamber 60, the susceptor electrode 8, the shaft 13, thebellows 11, the chamber bottom 10A, the chamber wall 10, and the upperchamber wall 10 a. The current then returns to the ground of theradiofrequency generator 1 via the chassis 21, the matching box 2, andthe shielding line of the feed line 1A.

Referring FIGS. 6 and 7, the following radiofrequency factors in theabove measuring region will affect the circuit of the radiofrequencycurrent which is supplied for plasma generation:

The inductance L_(f) and resistance R_(f) of the feed plate 3;

The plasma electrode capacitance C_(e) between the plasma excitationelectrode 4 and the susceptor electrode 8;

The inductance L_(C) and resistance R_(C) of the shaft 13;

The inductance L_(B) and resistance R_(B) of the bellows 11;

The inductance L_(A) and resistance R_(A) of the chamber wall 10;

The capacitance C_(A) between the gas feeding tube 17 and the plasmaexcitation electrode 4 separated by the insulator 17 a;

The capacitance C_(B) between the plasma excitation electrode 4 and thechassis 21; and

The capacitance C_(C) between the plasma excitation electrode 4 and theupper chamber wall 10 a.

As shown in FIG. 6, these radiofrequency factors are arranged to form anequivalent circuit so that the inductance L_(f) and resistance R_(f) ofthe feed plate 3, the plasma electrode capacitance C_(e) between theplasma excitation electrode 4 and the susceptor electrode 8, theinductance L_(C) and resistance R_(C) of the shaft 13, the inductanceL_(B) and resistance R_(B) of the bellows 11, and the inductance L_(A)and resistance R_(A) of the chamber wall 10 are connected in series inthat order while the resistance R_(A) is grounded. Moreover, thecapacitance C_(A), the capacitance C_(B), and the capacitance C_(C) areconnected in parallel between the resistance R_(f) and the plasmaelectrode capacitance C_(e), one end of each being grounded. In thisequivalent circuit, as shown in FIG. 8, the current I_(˜) supplied fromthe radiofrequency generator 1 is divided into a plasma current I_(e)flowing between the parallel plate electrodes 4 and 8 constituting theplasma electrode capacitance C_(e) and a loss current I_(x) which is ashunt component flowing into the other portions.I _(˜) =I _(e) +I _(x)  (14)

Since 26 times the plasma electrode capacitance C_(e) is greater thanthe loss capacitance C_(X) in the circuit of the plasma processingchamber 75 as described above, the impedance between the plasmaexcitation electrode 4 and the ground potential positions 17, 21, and 10a becomes larger than the impedance between the plasma excitationelectrode 4 and the susceptor electrode 8. Supposing the imaginary unitbeing j (j²=−1) and the angular frequency being ω (ω=2πf_(e) whereinf_(e) is a power frequency), the impedance Z (Ω) is represented byrelationship (11):Z∝−j/ωC  (11)wherein C is the capacitance. Thus, the impedance can be determined bydefining the capacitance. Since the current I is in inverse proportionto the impedance Z (Ω), an increase in the loss current I_(x) relativeto the plasma current I_(e) can be suppressed.

Even when a power frequency f_(e) which is higher than 13.56 MHz being agenerally used frequency is supplied, the proportion of the plasmacurrent I_(e) fed in the plasma space is increased.

Since 26 times the plasma electrode capacitance C_(e) is greater thanthe loss capacitance C_(X), the shunt components other than the currentflowing in the parallel plate electrodes 4 and 8 among the current I_(˜)supplied from the radiofrequency generator 1 can be controlled. Thus,the power can be effectively fed into the plasma generating space of theplasma processing chamber 60, and the effective power consumption in theplasma space can be increased compared with conventional plasmaprocessing apparatuses when the same frequency is supplied. In a layerdeposition process, the deposition rate will be improved. By setting theplasma electrode capacitance C_(e) and the loss capacitance C_(X) to theabove-described range, the overall radiofrequency characteristics of theactual apparatus can be controlled. Since such a control generates astable plasma, the plasma processing apparatus exhibits a stableoperation.

Since the loss current I_(x) is reduced, the effective power consumptionin the plasma space is improved compared with conventional plasmaprocessing apparatuses.

As the effective power consumed in the plasma space is increased, theuniformity in the plasma treatment on a workpiece in the planardirection can be improved. When applied to a deposition process,uniformity in the layer thickness can be achieved.

The improved power consumption in the plasma space also results inimprovements of layer characteristics, such as isolation voltage,etching resistance to etching solutions, and density or hardness of thedeposited layer. Herein, the layer density is represented by, forexample, the etching resistance in a BHF solution.

Since the plasma processing apparatus of this embodiment exhibits animproved power consumption efficiency compared to conventional plasmaprocessing apparatuses, the same process rate or layer characteristicscan be obtained with less power when the same frequency as the frequencyconventionally used is employed. Thus, the power loss can be decreased,the operating cost can be reduced, and the productivity can beincreased. Furthermore, the reduction in processing time leads toreduction in carbon dioxide emission.

In designing and manufacturing the plasma processing apparatus of thisembodiment, C_(e0) is set to a such value that 26 times C_(e0) is largerthan a loss capacitance C_(X0).

After reassembly of the plasma processing apparatus disassembled for thepurpose of transfer, after an adjustment work such as overhaul, partsreplacement, and assembly with alignment, or after plasma treatment ofworkpieces, a loss capacitance C_(X1) between the plasma excitationelectrode 4 and the ground potential positions measured at a later timet₁ is maintained at a such value that the absolute value of thedifference ΔC_(X) between C_(X0) and C_(X1) is maintained to be lessthan 10% of C_(X0). When the absolute value of ΔC_(X) is not less than10% of C_(X0), corrective action will be performed.

Examples of the corrective action for correcting C_(X1) are as follows:

(1) Adjusting the distance between and the areas of the plasmaexcitation electrode 4 and the susceptor electrode 8;

(2) Adjusting the overlapping area of the plasma excitation electrode 4and the upper chamber wall 10 a;

(3) Adjusting the material characteristics of insulator provided betweenthe plasma excitation electrode 4 and the upper chamber wall 10 a;

(4) Adjusting the thickness of the insulator provided between the plasmaexcitation electrode 4 and the upper chamber wall 10 a;

(5) Adjusting the distance between and the areas of the plasmaexcitation electrode 4 and the chassis 21;

(6) Adjusting the material characteristics of the insulator 17 a in thegas feeding tube 17; and

(7) Adjusting the length of the insulator 17 a.

In the plasma processing apparatus of this embodiment, C_(X1) ismaintained at such a value that the absolute value of the differenceΔC_(X) between C_(X1) and C_(X0) is less than 10% of C_(X0) even afterreassembly of the plasma processing apparatus disassembled for thepurpose of the transfer and after adjustment works. Accordingly, evenwhen an event such as above which would affect the radiofrequencycharacteristics occurs at a certain time, the radiofrequencycharacteristics remain unchanged before and after that time. Thus, theplasma processing apparatus 75 can be maintained within a required levelindicated by the loss capacitance C_(X), and the effective powerconsumed in the plasma processing space can be maintained at the samelevel.

Consequently, the same plasma process results can be obtained by usingthe same process recipe before and after the occurrence of the eventwhich would affect the radiofrequency characteristics. For example, whendeposition processes are performed in the plasma processing apparatus 75at a certain time interval, the same layer characteristics such as layerthickness, isolation voltage, and etching rate can be obtained despitethe time interval. In particular, when the absolute value of ΔC_(X)described above is maintained at a value less than 10% of C_(X), thevariation in deposition rate can be kept within 5% and variation in thelayer characteristics in the planar direction such as layer thicknessand isolation voltage can also be kept within 5% under the samedeposition conditions unaffected by the time interval, i.e., regardlessof whether there had been reassembly of the plasma processing apparatuspreviously disassembled for the purpose of the transfer or performanceof the adjustment works or regardless of the number of times used.

As a result, the overall radiofrequency characteristics of the plasmaprocessing apparatus which have not been considered before can beadjusted, and plasmas can be more stably generated. Thus, the plasmaprocessing apparatus 75 of this embodiment operates stably anduniformly.

Furthermore, when applied to a multi-chamber plasma processing apparatushaving a plurality of plasma processing chambers 60 and a plasma processsystem having a plurality of plasma processing apparatuses 75, theplasma processing chambers 60 in these apparatus and system can bemaintained to yield substantially the same plasma process results usingthe same process recipe.

Consequently, the process conditions can be determined without anexamination of the correlation between the external parameters and theprocess results from the evaluation method requiring actual depositionon substrates using an enormous amount of data.

Since the plasma processing apparatus can be evaluated by measuring theloss capacitance C_(X) between the plasma excitation electrode 4 and thegrounded potential positions, the time of an adjustment work required toeliminate variation in the treatment and to achieve substantially thesame process results using the same process recipe can be significantlyreduced compared to when an inspection method requiring actualdeposition on substrates is employed. Moreover, the plasma processingapparatus can be directly evaluated in situ in a shorter period of timeinstead of by a conventional two-stage evaluation requiring the steps offirst depositing layers on substrates and then evaluating the operationof the plasma processing apparatus based on these substrates. Generally,when the plasma processing apparatus is first installed, the plasmaprocessing apparatus is evaluated by the method requiring deposition onsubstrates to determine the process recipe for that plasma processingapparatus. Whereas conventional plasma processing apparatuses requireevaluation of all the plasma processing chambers, such an evaluationneeds to be performed in only one plasma processing chamber in thisembodiment since the radiofrequency characteristics of that chamber andthe other chambers are maintained to be the same.

Accordingly, in the evaluation method of this embodiment, a productionline need not be shut down for several days to several weeks to checkand evaluate the operation of the plasma processing apparatus. Theproduction line, therefore, has high productivity, and the cost forsubstrates for inspection, cost for processing the substrates forinspection, and labor cost for the workers involved in the adjustmentwork can be reduced.

The loss capacitance C_(X) as the radiofrequency characteristic of theupper component 19 of the plasma processing apparatus 75 may be measuredusing a fixture comprising a plurality of conductive wires 101 a to 101h of matching impedance and a probe attachment 104 to which one end ofeach of the plurality of conductive wires 101 a to 101 h is attached, asshown in FIG. 9.

The probe attachment 104 is formed, for example, by shaping a 50 mm×10mm×0.5 mm copper plate into a clamping portion 106 and a ring portion.The diameter of the ring portion is determined so that the ring portionis attachable to the circumference of the probe 105. One end of each ofthe conductive wires 101 a to 101 h is soldered to the probe attachment104 to be electrically connected thereto.

Terminals (attachments) 102 a to 102 h which are attachable to anddetachable from an object (upper component 19) to be measured areinstalled at the other ends of the conductive wires 101 a to 101 h.

In using this fixture, the probe 105 is inserted into the ring portionof the probe attachment 104, and the probe 105 and the probe attachment104 are clamped by the clamping portion 106. The conductive wires 101 ato 101 h are detachably screwed to the measured object in asubstantially symmetrical manner about a point through the terminals 102a to 102 h, as shown in FIG. 10.

The conductive wires 101 a to 101 h may be made of, for example,aluminum, copper, silver, or gold, or may be plated by silver or goldhaving a thickness of 50 μm or more.

The method for measuring the loss capacitance C_(X) using this fixtureis now explained with reference to FIGS. 1, 9, and 10.

First, the radiofrequency generator 1 and the matching box 2 are removedfrom the rest of the plasma processing apparatus 75. Since the uppercomponent 19 is the measured region, the upper component 19 is separatedfrom the chamber wall 10. The conductive line 110 of the probe 105 of animpedance meter (RF characteristic meter) AN is then connected to thefeed plate 3. The terminals 102 a to 102 h connected to the conductivewires 110 a to 101 h of the fixture are screwed to the chassis 21 of theplasma processing chamber 75 in a symmetrical manner about the feedplate 3 using screws 114. After the fixture is set as above, a measuringsignal is fed to the conductive line 110 of the impedance meter AN tomeasure the impedance of the paths between the point PR and each of thegrounded potential positions.

By using the fixture, a uniform current flows in the measured objectregardless of the size of the measured object or the distance betweentwo points to be measured. Moreover, by using the dedicated fixture, theimpedance of the measured object can be measured accurately since theresidual impedance due to probing affecting the impedance can besuppressed. Thus, the loss capacitance C_(X) as the radiofrequencycharacteristic can be measured accurately.

Since only capacitance instead of general radiofrequency characteristicsis measured in this plasma processing apparatus of this embodiment, aninexpensive meter can be used.

Although the substrate 16 is placed on the susceptor electrode 8 and theplasma electrode capacitance C_(e) and the loss capacitance C_(X) areset in relation to the plasma excitation electrode 4, the substrate 16may be placed on the plasma excitation electrode 4 in the plasmaprocessing apparatus of this embodiment.

Second Embodiment

A plasma processing apparatus in accordance with a second embodiment ofthe present invention will now be described with reference to theattached drawings.

FIG. 11 is a cross-sectional view illustrating an outline configurationof the plasma processing apparatus 95 of this embodiment, and FIG. 12 isa schematic view of an upper component 19 in FIG. 11.

The plasma processing chamber unit 95 of this embodiment is of adual-frequency excitation type. This plasma processing apparatus 95differs from the plasma processing chamber 75 of the first embodimentshown in FIG. 1 in that power is also supplied to the susceptorelectrode 8 and that a measuring terminal 61 is provided. Anotherdifference is the setting of the plasma electrode capacitance C_(e) andthe loss capacitance C_(X). Other corresponding components are referredto as the same reference numerals and symbols and the descriptionthereof is omitted.

Referring to FIG. 11, the plasma processing apparatus 95 of thisembodiment has a susceptor shield 12 disposed under a susceptorelectrode 8 and a bellows 11 for vertically moving the susceptorelectrode 8 and the susceptor shield 12. The distance between a plasmaexcitation electrode 4 and the susceptor electrode 8 is therebyadjustable. The shaft 13 and the susceptor electrode 8 are electricallyisolated from the susceptor shield 12 by a gap between the susceptorshield 12 and the susceptor electrode 8 and by insulators 12C providedaround the shaft 13. The insulators 12C also maintain high vacuum in theplasma chamber 60. The susceptor electrode 8 is connected to a secondradiofrequency generator 27 through a feed plate 28 connected to thebottom end of a shaft 13 and a matching circuit 25 contained in aconductive matching box 26.

The feed plate 28 is covered by a chassis 29 connected to the bottom endof a cylindrical support 12B of the susceptor shield 12. The chassis 29is connected to the matching box 26 by a shielding line of a feed line27A which is a coaxial cable, and is grounded together with the matchingbox 26. Thus, the susceptor shield 12, the chassis 29, and the matchingbox 26 have the same DC potential.

The matching circuit 25 matches the impedance between the secondradiofrequency generator 27 and the susceptor electrode 8. Referring toFIG. 11, the matching circuit 25 has passive elements such as a tuningcoil 30 and a tuning capacitor 31 connected in series between the secondradiofrequency generator 27 and the feed plate 28, and a load capacitor32 connected in parallel with the tuning coil 30 and the tuningcapacitor 31. One end of the load capacitor 32 is connected to thematching box 26. Accordingly, the matching circuit 25 has substantiallythe same configuration as that of the matching circuit 2A. The matchingbox 26 is set to a ground potential through the shielding line of thefeed line 27A, thereby the end of the load capacitor 32 being grounded.Alternatively, another tuning coil may be connected in series to thetuning coil 30, and another load capacitor may be connected in parallelto the load capacitor 32.

The feed plate 28 may be identical to the feed plate 3. The input end ofthe feed plate 28 is screwed to a terminal extending from the matchingcircuit 25, and the output end is screwed to the shaft 13.

The plasma processing apparatus 95 is designed and produced so that fivetimes the plasma electrode capacitance C_(e0) between the parallel plateelectrodes 4 and 8 is larger than the loss capacitance C_(X0) at a timet₀.

Furthermore, the performance of the plasma processing apparatus 95 whichis reassembled at a delivery site is maintained such that the absolutevalue of the difference ΔC_(X) between the loss capacitance C_(X1) at alater time t1 and the loss capacitance C_(X0) at the time t₀ is lessthan 10% of the loss capacitance C_(X0), wherein the loss capacitanceC_(X1) and the loss capacitance C_(X0) are measured between the plasmaexcitation electrode connected to the radiofrequency generator andground potential positions which are DC-grounded.

The measuring range in the plasma processing apparatus 95 of thisembodiment includes the downstream side of the output terminal positionPR shown in FIGS. 11 and 12 toward the plasma excitation electrode 4. Animpedance measuring terminal 61 extends from a branch point B at theinput terminal of the feed plate 3 to the exterior of the matching box2.

A switch SW1 is provided between the matching circuit 2A and the feedplate 3 and in the vicinity of the output terminal position PR and aswitch SW2 is provided between the impedance measuring terminal 61 andthe feed plate 3.

The impedance characteristics from the impedance measuring terminal 61side when the impedance measuring terminal 61 is connected by the switchSW2 and the impedance characteristics from the matching circuit 2A sidewhen the matching circuit 2A is connected by the switch SW1 are set tobe equal to each other. That is, as shown in FIG. 11, the impedance Z₁measured in the vicinity of the switch SW1 and the impedance Z₂ measuredin the vicinity of the switch SW2 are set to be equal to each other.

In other words, the impedance Z₁ from the output terminal position PR tothe branch point B when the switch SW1 is closed and the switch SW2 isopen is set to be equal to the impedance Z₂ from the impedance measuringterminal 61 to the branch point B when the switch SW2 is closed and theswitch SW1 is opened.

A probe of an RF characteristic meter AN is detachably connected to theimpedance measuring terminal 61. The probe is also detachably connectedto the ground position, for example, a chassis 21 of the plasmaprocessing apparatus 95.

In the plasma processing apparatus 95 of this embodiment, while closingthe switch SW1 and opening the switch SW2, a substrate 16 to be treatedis placed on the susceptor electrode 8, radiofrequency voltages areapplied to the plasma excitation electrode 4 and the susceptor electrode8 from a first radiofrequency generator 1 and the second radiofrequencygenerator 27, respectively, while a reactive gas is fed into a plasmachamber 60 through a gas feeding tube 17 and shower holes 7 to generatea plasma, and plasma processing such as deposition or the like isperformed on the substrate 16. During this process, a radiofrequencyvoltage of approximately 13.56 MHz or more, for example, 13.56 MHz,27.12 MHz, or 40.68 MHz, is supplied from the first radiofrequencygenerator 1. The second radiofrequency generator 27 may supply eitherthe same radiofrequency power as does the first radiofrequency generator1 or a different radiofrequency of, for example, 1.6 MHz.

The plasma electrode capacitance C_(e) and the loss capacitance C_(X) asradiofrequency characteristics of the plasma processing apparatus 95 ofthis embodiment are defined and measured as in the first embodiment.That is, the plasma electrode capacitance C_(e) and the loss capacitanceC_(X) are defined as shown in FIGS. 5 and 13.

FIG. 13 is an equivalent circuit diagram for measuring the plasmaelectrode capacitance C_(e) and the loss capacitance C_(X) of the plasmaprocessing chamber 15 shown in FIG. 11, and FIG. 5 is an equivalentcircuit diagram for measuring the plasma electrode capacitance C_(e) andthe loss capacitance C_(X) of the upper component 19 shown in FIG. 12.

In this embodiment, the loss capacitance C_(X) of the plasma processingapparatus 95 means that of the upper component 19 which is measured atthe output terminal position PR. As shown in FIG. 11, the impedance Z₁in the vicinity of the switch SW1 is equal to the impedance Z₂ in thevicinity of the switch SW2. Thus, the radiofrequency characteristic(impedance) of the upper component 19 measured at the output terminalposition PR is equal to the radiofrequency characteristic (impedance)thereof measured at the impedance measuring terminal 61.

In the first embodiment, the matching circuit 2A is mechanicallydetached when the radiofrequency characteristics are measured. In thisembodiment, however, the matching circuit 2A is electricallydisconnected from the measuring range by the switch SW1, as shown inFIGS. 11 and 12; hence, the radiofrequency characteristics of the uppercomponent 19 can be readily measured without mechanically detaching thematching circuit 2A.

Referring to FIG. 13, the radiofrequency electrical factors affectingthe above-described measuring region of the plasma processing apparatus95 are as follows:

The inductance L_(SW) and resistance R_(SW) of the switch SW2;

The inductance L_(f) and-resistance R_(f) of the feed plate 3;

The plasma electrode capacitance C_(e) between the plasma excitationelectrode 4 and the susceptor electrode 8;

The contribution of the matching circuit 25;

The capacitance C_(s) between the susceptor electrode 8 and a susceptorshield 12;

The inductance L_(C) and resistance R_(C) of a cylindrical support 12Bof the susceptor shield 12;

The inductance L_(B) and resistance R_(B) of a bellows 11;

The inductance L_(A) and resistance R_(A) of a chamber wall 10;

The capacitance C_(A) between a gas feeding tube 17 and the plasmaexcitation electrode 4 via an insulator 17 a;

The capacitance C_(B) between the plasma excitation electrode 4 and thechassis 21; and

The capacitance C_(C) between the plasma excitation electrode 4 and theupper chamber wall 10 a.

That is, the radiofrequency characteristics in the measuring modeinclude the contribution of the switch SW2 which corresponds to theswitch SW1 closed in the operation mode. Since the impedance Z₁ is equalto the impedance Z2, the radiofrequency characteristics measured at theimpedance measuring terminal 61 precisely reflect the state of theradiofrequency circuit during plasma generation in the operation mode.

A probe 105 shown in FIG. 9 and connected to the RF characteristic meterAN is connected to the impedance measuring terminal 61 and a groundposition, for example, the chassis 21 of the plasma processing apparatus95. While closing switch SW2 and opening the switch SW1, the losscapacitance C_(X) as the radiofrequency characteristic of the uppercomponent 19 is measured with the RF characteristic meter AN.

As shown in FIG. 12, the loss capacitance C_(X) represents thecapacitance component generated for the plasma excitation electrode 4 inthe upper component 19 which is electrically disconnected from theplasma processing apparatus 95.

The loss capacitance C_(X) is the sum of the capacitance components forcurrents which flow in regions other than the path from the plasmaexcitation electrode 4 to the susceptor electrode 8. That is, the losscapacitance C_(X) is the sum of the capacitance components between theplasma excitation electrode 4 and individual ground potential positionswhich are DC grounded. Herein, the individual ground potential positionsindicate chamber components at the ground potential other than thesusceptor electrode 8 of the plasma processing apparatus 95. That is,the individual ground potential positions include the susceptor shield12, the cylindrical support 12B, the shaft 13, the bellows 11, thechamber bottom 10A, the chamber wall 10, the upper chamber wall 10 a,the chassis 21, the matching box 2, the gas feeding tube 17 at the gassupply side from the insulator 17 a, and the sheath line of theradiofrequency power feed line 1A. Specifically, as in the firstembodiment shown in FIG. 4, the gas feeding tube 17, the chassis 21, theupper chamber wall 10 a are taken into consideration as the losscapacitance C_(X). That is, the ground potential positions include thesusceptor shield 12, the cylindrical support 12B, the shaft 13, thebellows 11, the chamber bottom 10A, the chamber wall 10, the upperchamber wall 10 a, the chassis 21, the matching box 2, the gas feedingtube 17 at the gas source side rather than the insulator 17 a, and thesheath line of the radiofrequency power feed line 1A. Specifically, asshown in FIG. 4, the gas feeding tube 17, the chassis 21, the upperchamber wall 10 a are taken into consideration as the loss capacitanceC_(X) at the portions opposing the plasma excitation electrode 4.

The loss capacitance C_(X) is defined by the sum of the capacitanceC_(A) between the plasma excitation electrode 4 and the gas feeding tube17 separated by the insulator 17 a, the capacitance C_(B) between theplasma excitation electrode 4 and the chassis 21, and the capacitanceC_(C) between the plasma excitation electrode 4 and the upper chamberwall 10 a.

The plasma electrode capacitance C_(e) between the parallel plateelectrodes 4 and 8 is determined by the areas of (the sizes of) and thedistance between the plasma excitation electrode 4 and the susceptorelectrode 8.

In the plasma processing apparatus 95 of this embodiment, the losscapacitance C_(X) is less than 5 times the plasma electrode capacitanceC_(e).

The plasma electrode capacitance C_(e) and the loss capacitance C_(X)may be set according to methods (1) to (7) described in the firstembodiment.

Moreover, in this embodiment, the plasma electrode capacitance C_(e)between the plasma excitation electrode 4 and the susceptor electrode 8is set according to an effective interelectrode distance δ in the plasmaspace.

FIG. 14 is a schematic view of the state of the space between twoelectrodes when a plasma is generated.

The plasma excitation electrode 4 and the susceptor electrode 8 are of aparallel plate type and have a distance d. The sum of the distance δ_(a)between the plasma excitation electrode 4 and a plasma region P, whichcan be visually recognized during plasma emission, and the distanceδ_(b) between the susceptor electrode 8 and the plasma region P isrepresented by δ. In other words, the distance δ_(a) of the nonplasmaregion between the plasma excitation electrode 4 and the plasma region Pand the distance δ_(b) of the nonplasma region between the plasma regionP and the susceptor electrode 8 satisfy relationship (6):δ_(a)+δ_(b)=δ  (6)

An apparent capacitance C_(e)″ between the electrodes 4 and 8 duringplasma emission will be derived from the distance d between theelectrodes 4 and 8 and the sum δ of the distances δ_(a) and δ_(b) of thenonplasma regions between the electrodes 4 and 8, as follows.

The plasma region P functions as a conductor during plasma emission;hence, the distance between the electrodes 4 and 8 can be regarded as δduring the plasma emission. The apparent capacitance C_(e)″ between theparallel plate electrodes 4 and 8 during plasma emission is inverselyproportional to the effective distance δ between the electrodes 4 and 8,and the actual interelectrode capacitance C_(e) when the plasma is notemitted is inversely proportional to the actual distance d between theelectrodes 4 and 8. Thus, the apparent capacitance C_(e)″ during plasmaemission becomes d/δ times the actual interelectrode capacitance C_(e)as shown in relationship (7):C_(e)∝1/d C_(e)″∝1/δ∴C_(e)″∝d/δ·C_(e)  (7)

Accordingly, in this embodiment, five times the actual interelectrodecapacitance C_(e) may be greater than the loss capacitance C_(X). Thatis, the actual interelectrode capacitance C_(e) may be set such that5×d/δ times the actual interelectrode capacitance C_(e) is greater thanthe loss capacitance C_(X). Power consumption during plasma emission isthereby further improved.

The plasma electrode capacitance C_(e0) is designed such that the 5times the plasma electrode capacitance C_(e)″ during the plasma emissionmode (5×d/δ times the plasma electrode capacitance C_(e)) is larger thanthe loss capacitance C_(X) defined as above. After reassembling theapparatus at a customer site, plasma-treating workpieces using theapparatus, and performing adjustment works such as overhauling, partsreplacement, assembly with alignment and the like, the plasma processingapparatus is maintained such that the difference ΔC_(X) between the losscapacitance C_(X1) at the later time t1 is less than 10% of the losscapacitance C_(X0) at the time t₀. If the difference ΔC_(X) is not lessthan 10% of the loss capacitance C_(X0), a corrective action isperformed.

The loss capacitance C_(X) may be corrected, for example, according tomethods (1) to (7) described in the first embodiment.

The plasma processing apparatus of this embodiment has substantially thesame advantages as those in the first embodiment. Moreover, thedetachable RF characteristic meter AN is connected to the impedancemeasuring terminal 61 and the switches SW1 and SW2 having impedances Z₁and Z₂, respectively, which are equal to each other, are provided. Thus,the radiofrequency characteristics such as the plasma electrodecapacitance C_(e) and the loss capacitance C_(X) can be determined onlyby changing the switches SW1 and SW2 without detaching the plasmaprocessing chamber from the matching circuit 2A.

Moreover, in this embodiment, the loss capacitance C_(X) is less than 5times the plasma electrode capacitance C_(e). Thus, the electrical powerwhich is required for the uniformity in the processing rate (depositionrate), the layer thickness, and layer characteristics, such as isolationvoltage, in the planar direction can be reduced, resulting in reducedoperational costs.

In this embodiment, the two switches SW1 and SW2 are provided. Since theessential feature in this embodiment is that the impedance from thebranch to the measuring point PR is equal to the impedance from thebranch to the probe, this requirement may be satisfied using one switch.

In addition to the plasma processing apparatus using the parallel platetype electrodes 4 and 8, the present invention can be applied to aninductive coupled plasma (ICP) excitation type plasma processingapparatus, a radial line slot antenna (RLSA) type plasma processingapparatus, and a reactive ion etching (RIE) type processing apparatus.

Target components may be provided in place of the parallel plateelectrodes 4 and 8 to perform plasma sputtering.

Third Embodiment

A performance management system for a plasma processing apparatusaccording to a third embodiment of the present invention will now beexplained with reference to the drawings.

FIG. 15 is a schematic diagram showing the configuration of aperformance management system for a plasma processing apparatusaccording to a third embodiment of the present invention. FIG. 16 is aflowchart illustrating steps of providing evaluation information in thisperformance management system.

The performance management system shown in FIG. 15 includes a server210, a customer I/O device 220, a communication line 230 for linking theserver 210 and the customer I/O device 220, and an output device 240 ata delivery site, the output device 240 being linked to the server 210.

The server 210 is under control of a supplier, for example, amanufacturer of the plasma processing apparatus, a distributor, or amaintenance company and is preferably located at the site of thesupplier. The server 210 is preferably provided with a high-speedcomputer for simultaneously providing services to a plurality ofcustomer I/O devices 220 and a high-capacity memory unit for storinginformation regarding a variety of services and plasma processingapparatuses at customer sites. Examples of such machines are largecomputers and high-performance workstations.

The server 210 includes a computer 211, a memory unit 212 linked to thecomputer 211, and a transmitter/receiver 213 linked to the communicationline 230. The server 210 is linked to the output device 240 at thedelivery site.

The customer I/O device 220 is used by the customer and a maintenanceengineer visiting the customer. The customer I/O device 220 may beinstalled at the customer site or may be a portable device. Any type ofthe customer I/O device 220 can be used as long as the device cantransmit/receive signals to/from the server 210 via the communicationline 230. Examples of such devices are personal computers, dedicatedterminals, and telephone machines.

The customer I/O device 220 includes a body 221 and atransmitter/receiver 223 linked to the communication line 230.

No limit is imposed as to the medium or the type of communication line230 as long as the remote server 210 and the customer I/O device 220 cantransmit/receive signals. Examples of the communication media for thecommunication lines 230 are cables, optical fiber lines, and satellitecircuits. Examples of the types of the communication line are telephoneline network and the Internet.

Referring to FIG. 15, the operation of this embodiment will now bedescribed according to the flowchart shown in FIG. 16.

To start the performance evaluation using this system, a user, forexample, a customer or a maintenance engineer who visits the customer,of the performance management system first measures C_(X1) and C_(e1) ofthe plasma processing apparatus which is delivered to the customer siteor is already in operation at the customer site. The value C_(X1) is theloss capacitance between the plasma excitation electrode 4 and thegrounded potential positions which are DC grounded measured at a time t₁which is later than a time t₀, and the value C_(e1) is the plasmaelectrode capacitance between the plasma excitation electrode 4 and thesusceptor electrode 8 measured at a time t₁. The observed values ofC_(X1) and C_(e1) are then inputt through the customer I/O device 220(Step 301) and transmitted to the server 210 via the communication line230.

The server 210 retrieves from the memory unit 212 data 500 containingC_(X0) and C_(e0), C_(X0) being the reference loss capacitance betweenthe plasma excitation electrode 4 and the grounded potential positionswhich are DC-grounded measured at the time t₀, and C_(e0) being thereference plasma electrode capacitance between the plasma excitationelectrode 4 and the susceptor electrode 8 measured at the time t₀. Basedon these values, the server calculates the absolute value |ΔC_(X)|between C_(X0) and C_(X1) (Step 302).

The loss capacitance C_(X0) is the reference loss capacitance set at thedelivery site before the plasma processing apparatus is disassembled forthe purpose of the transfer. For example, the loss capacitance C_(X0) isset at such a value that 26 times the plasma electrode capacitanceC_(e0) is larger than the loss capacitance C_(X0). Preferably, the losscapacitance C_(X0) is set at such a value that 7 times the plasmaelectrode capacitance C_(e0) is larger than the loss capacitance C_(X0),and, more preferably, the loss capacitance C_(X0) is set at such a valuethat 5 times the plasma electrode capacitance C_(e0) is larger than theloss capacitance C_(X0).

The server 210 then compares |ΔC_(X)| with C_(X0) to evaluate theperformance of the plasma processing apparatus. More specifically, theserver 210 determines that the plasma processing apparatus satisfies therequired level of the performance when |ΔC_(X)| is less than 10% ofC_(X0). The server 210 determines that the plasma processing apparatusdoes not satisfy the required level of the performance when |ΔC_(X)| isnot less than 10% of C_(X0) (Step 303).

Next, the server 210 provides the results of the performance evaluationto both the customer I/O device 220 and the output device 240 located atthe location of the supplier (Step 304).

The server 210 transmits print, display, or sound alarm signals to thecustomer I/O device 220. When the server 210 determines that therequired level of performance is maintained, the server 210 outputsthrough the customer I/O device 220, for example, a message “Thisapparatus maintains the required performance level. Please continueusing.” When the server 210 determines that the required level ofperformance is not maintained, the server 210 outputs through thecustomer I/O device 220, for example, a message “This apparatus may notbe maintained at the required performance level. Please adjust thisapparatus according to the manual.” These messages may be output for thecustomer or the maintenance engineer in the form of printing, display ona screen, or sound.

Also, the server 210 transmits print, display, or sound alarm signals tothe output device 240 when the server 210 determines that the requiredlevel of performance is not maintained. The output device 240 outputs amaintenance command in the form of printing, message display, signaloutput, or alarm sound.

Preferably, the identification number of the plasma processing chamberis received from the customer I/O device 220 and is output through thecustomer I/O device 220 in order for the supplier to identify the plasmaprocessing apparatus requiring maintenance. Alternatively, theidentification number or phone number of the customer I/O device 220 maybe used to determine the identification number of the plasma processingapparatus and to output the results from the output device 240.

As a result, the customer or the maintenance engineer who visits thecustomer can evaluate the performance of the plasma processing apparatuswithout actually operating the plasma processing apparatus to depositlayers on substrates and inspecting these substrates.

Moreover, the plasma processing apparatus can be directly evaluated insitu in a shorter period of time instead of by a conventional two-stageevaluation requiring the steps of first depositing the substrate andthen evaluating the operation of the plasma processing apparatus basedon the deposited substrates. Generally, when the plasma processingapparatus is first installed, the plasma processing apparatus isevaluated by the method requiring deposition on substrates to determinethe process recipe for that plasma processing apparatus. Whereasconventional plasma processing apparatuses require evaluation of all theplasma processing chambers, such an evaluation needs to be performed inonly one plasma processing chamber of the multi-chamber plasmaprocessing apparatus in this embodiment since the radiofrequencycharacteristics of that chamber and the other chambers are maintained tobe the same.

Thus, the method of this embodiment does not require shutdown of theproduction line for several days to several weeks to validate andevaluate the performance and operation of the plasma processingapparatus, thereby improving productivity of the production line. Also,the cost for substrates for inspection, cost for processing thesubstrates for inspection, and labor cost for the workers involved inthe adjustment work can be reduced.

Moreover, the malfunctioning of the plasma processing apparatus at thecustomer site can be immediately detected by the manufacturer, etc., atthe delivery site through the maintenance command, providing betterrepair service to the customer.

The upper limits which constitute the basis for the evaluationinformation may differ between the server 210 and the customer I/Odevice 220. For example, the upper limit for the evaluation informationtransmitted to the customer I/O device 220 may be set at 10% of C_(X0)while the upper limit for the evaluation information transmitted to theoutput device 240 located at the location of the supplier may be set at3% of C_(X0). In this manner, the signal indicating that the requiredperformance level is not satisfied is transmitted to the customer I/Odevice 220 when |ΔC_(X)| is not less than 10% of C_(X0) and to theoutput device 240 located at the location of the supplier when |ΔC_(X)|is not less than 3% of C_(X0) When the evaluation standard is tighter atthe output device located at the delivery site than at the customer I/Odevice as in the above, maintenance service can be provided before theperformance of the plasma processing apparatus is significantly varied.In other words, the maintenance service can be more preventive.

Fourth Embodiment

Another performance management system for a plasma processing apparatusin accordance with a fourth embodiment will now be described withreference to the drawings.

FIG. 17 is a block diagram of a performance management system for aplasma processing apparatus of this embodiment, and FIG. 18 is aflowchart illustrating steps of providing evaluation information in thisperformance management system. In these drawings, the components shownin FIGS. 15 and 16 are referred to with the same reference numerals andthe description thereof is omitted.

The performance management system shown in FIG. 17 includes a server210, a customer I/O device 220, a communication line 230 linking theserver 210 and the customer I/O device 220, and an output device 240located at the site of the supplier, the output device 240 being linkedto the server 210. The performance management system further includes acapacitance meter 260 for measuring capacitance, the capacitance meter260 being connected to a plasma processing apparatus 250.

In this embodiment, the output terminal of the capacitance meter 260 isconnected to the customer I/O device 220 so that the loss capacitanceC_(X) as the radiofrequency characteristic of the plasma processingapparatus 250 measured using the capacitance meter 260 is directlytransmitted to the server 210 via the customer I/O device 220 and thecommunication line 230 without input by an operator. The customer I/Odevice 220 is programmed so to read the values measured with thecapacitance meter 260 upon the input of the identification number S of aplasma processing chamber.

The procedure in this embodiment will now be described based on theflowchart shown in FIG. 18, with reference to FIG. 17.

A user of this performance management system, for example, a customer ora maintenance engineer who visits the customer, connects the capacitancemeter 260 to the customer I/O device 220, and inputs the identificationnumber S of the plasma processing chamber from the customer I/O device220. The loss capacitance C_(X1) between the electrode connected to aradiofrequency generator and ground potential positions measured at atime t₁ and the plasma electrode capacitance C_(e1) between theelectrode connected to the radiofrequency generator and a counterelectrode measured at the time t₁ are measured and automatically inputinto the customer I/O device 220 from the capacitance meter 260according to the program stored in the customer I/O device 220 (Step401).

The identification number S, C_(X1), and C_(e1) are transmitted to theserver 210 via the communication line 230.

The server 210 then retrieves from a memory device 212 information 600containing unique values of C_(X0) and C_(e0) associated with thatidentification number S, C_(X0) being the loss capacitance between theelectrode connected to the radiofrequency generator and the groundpotential positions which are DC grounded measured at a time t₀ andC_(e0) being the plasma electrode capacitance between the electrodeconnected to the radiofrequency generator and the counter electrodemeasured at the time t₀. The server 210 calculates the absolute value|ΔC_(X)| of the difference between C_(X0) and C_(X1) based on thesevalues (Step 402).

Herein, C_(X0) and C_(e0) stored in the memory device 212 are uniquelyassociated with the identification number S. In other words, C_(X0) andC_(e0) are the radiofrequency characteristics unique to the individualplasma processing chamber and are actually measured or set during themanufacturing process.

The server 210 compares |ΔC_(X)| with C_(X0) to evaluate the performanceof the plasma processing apparatus. When |ΔC_(X)| is less than 10% ofC_(X0), the server 210 determines that the plasma processing apparatusmaintains a required level of performance. When |ΔC_(X)| is not lessthan 10% of C_(X0), the server 210 determines that the plasma processingapparatus does not maintain the required level of performance (Step403).

Next, the server 210 provides the results of the performance evaluationto both the customer I/O device 220 and the output device 240 at thedelivery site (Step 404).

The server 210 transmits print, display or sound alarm signals to thecustomer I/O device 220. When the server 210 determines that therequired level of performance is maintained, the server 210 outputs, forexample, a message “This apparatus maintains the required level ofperformance. Please continue using.” When the server 210 determines thatthe required level of performance is not maintained, the server 210outputs, for example, a message “This apparatus may not maintain therequired level of performance. Please adjust this apparatus according tothe manual.” These messages may be output for the customer or themaintenance engineer in the form of printing, display on a screen, orsound.

Also, the server 210 transmits print, display, or sound alarm signals tothe output device 240 when the server 210 determines that the requiredlevel of performance is not maintained. The output device 240 outputs amaintenance command by printing or displaying a message or providing asignal or alarm. The server 210 also provides the identification numberS of the plasma processing chamber to the output device 240 so that theapparatus requiring the maintenance can be specified at the deliverysite.

The performance management system for the plasma processing apparatusaccording to this embodiment exhibits the same advantages as those inthe third embodiment. Since the observed values are stored in connectionwith the identification numbers S of the plasma processing chambers, theplasma processing chambers can be more precisely controlled. Thesupplier, such as a manufacturer and so on can immediately specify atits own location the malfunctioning plasma processing chamber.

In a plasma processing apparatus having a plurality of the plasmaprocessing chambers or in a plasma processing system having a pluralityof plasma processing apparatuses, it is preferable that the sameradiofrequency characteristics be set for these plasma processingchambers so that substantially the same film characteristics areachieved using the same process recipe under the same operatingconditions. In this respect, C_(X0) and C_(e0) of the plasma processingchambers are preferably set at the same values. However, C_(X0) andC_(e0) may be set significantly different from one another among theseplasma processing chambers depending on various factors at the customersite, etc.

Fifth Embodiment

Another performance management system for a plasma processing apparatusin accordance with a fifth embodiment will now be described withreference to the drawings.

The system configuration of the performance management system in thisembodiment is also shown in FIG. 17.

The configuration of this embodiment differs from that of the fourthembodiment in that the server 210 stores maintenance engineerinformation 601. The maintenance engineer information 601 includesperformance levels which includes fault levels having predeterminedranges and names of the service engineers registered according to thefault levels. Table 1 shows an example of the maintenance engineerinformation 601.

TABLE 1 Maintenance Engineer Information 601 |ΔC_(x)| Performance LevelMaintenance Engineer |ΔC_(x)| ≧ 100% Fault level 1 Engineer A, EngineerB 100% > |ΔC_(x)| ≧ 50% Fault level 2 Engineer C, Engineer D  50% >|ΔC_(x)| ≧ 10% Fault level 3 Engineer E, Engineer F 10% > |ΔC_(x)| ≧ 3%Good Engineer G 3% > |ΔC_(x)| Best —

The procedure in this embodiment will now be described based on theflowchart shown in FIG. 19, with reference to FIG. 17. The descriptionregarding Steps 501 and 502 in the flowchart shown in FIG. 19 areomitted because these steps are the same as Steps 401 and 402,respectively, in FIG. 18.

The server 210 calculates |ΔC_(X)| in Step 502 and evaluates theperformance level of the plasma processing apparatus with reference tothe engineer information 601. When the server 210 determines that theapparatus is in any one of fault levels 1 to 3, the server 210 calls upthe maintenance engineer's names associated with that fault levelcontained in the engineer information 601 (Step 503).

The server 210 provides the relevant performance level to both thecustomer I/O device 220 and the output device 240 at the delivery site(Step 504).

The relevant performance level is transmitted to the customer I/O device220 by sending print signals, display signals, or voice signals.

When the performance level is “best”, the customer I/O device 220outputs a message, for example, “This apparatus maintains a requiredlevel of performance. Please continue using.” When the performance levelis “good”, the customer I/O device 220 outputs a message “This apparatusstill maintains the required level of performance, but will needinspection soon.” When the performance level is any one of fault levels1 to 3, the customer I/O device 220 outputs a message “This apparatus isat fault level 2. Please request your maintenance engineer foradjustment.” These messages may be made available to the customer or aservice engineer in the form of print-out, display on the screen, orvoice.

The server 210 also outputs the performance level, the maintenanceengineer's names corresponding to the performance level, and amaintenance command through the output device 240 at the delivery site.

According to the performance management system for the plasma processingapparatus of this embodiment, the maintenance command is output with thefault level and the maintenance engineer's names corresponding to thefault level at the location of the supplier.

Thus, the fault level of the plasma processing apparatus at a distantplace can be identified at the location of the supplier, and amaintenance engineer having skill suitable for the fault level can bereadily dispatched, thus achieving rapid and adequate maintenanceservices with an efficient engineer distribution. Accordingly, themaintenance system after installation of the plasma processing apparatuscan be operated effectively.

No limit is imposed as to the type of the plasma processing apparatusmanaged by the management system of this embodiment. The managementsystem of this embodiment can be applied to the plasma processingapparatuses according to the above-described first and secondembodiments, to the plasma processing apparatus according to ninth andtenth embodiment described below, and to a plasma processing system ofan eleventh embodiment described below.

Sixth Embodiment

Next, a performance validation system of a plasma processing apparatusaccording to a sixth embodiment of the present invention will bedescribed with reference to the drawings. In the following description,a person who distributes and maintains the plasma processing apparatusis referred to as a “maintenance engineer”.

FIG. 20 is a diagram illustrating the configuration of the performancevalidation system of the plasma processing apparatus of this embodiment.

Referring to FIG. 20, the performance validation system comprises acustomer terminal (client terminal) C1, an engineer terminal (clientterminal) C2, a server computer (hereinafter simply referred to as“server”) S which functions as operational performance informationproviding means, a database computer (hereinafter simply referred to as“database”) D which stores information, and a public line N. Thecustomer terminal C1 and the engineer terminal C2, the server S, and thedatabase D are linked to one another via the public line N.

The terminals C1 and C2 communicate with the server S using a widespreadInternet communication protocol, such as TCP/IP or the like. Thecustomer terminal C1 serves as a customer-side information terminal forvalidating, via the public line N, the state of the performance of theplasma chamber which the customer purchased from the maintenanceengineer. An information web page which is a “plasma chamber performanceinformation page” stored in the server S is provided through thecustomer terminal C1. The maintenance engineer uploads “C_(X0)information” which is the information on the loss capacitance between anelectrode connected to a radiofrequency generator and ground potentialpositions which are DC-grounded measured at a time t₀, and “C_(e0)information” which is the information on the plasma electrodecapacitance between the electrode connected to the radiofrequencygenerator and a counter electrode to the server S through the engineerterminal C2. The “C_(X0) information” and “C_(e0) information” are partof the “performance information”. The engineer terminal C2 also receivesE-mail sent from the customer through the customer terminal C1.

In this embodiment, the plasma processing apparatus or system hassubstantially the same structure as those of the first and secondembodiments. The structure of the apparatus, such as the number ofchambers and the like, can be set as desired.

The server S communicates through a modem when the public line N is ananalog line or through a dedicated terminal adapter or the like when thepublic line N is a digital line such as an integrated services digitalnetwork (ISDN).

The server S is a computer that provides performance information. Theserver S transmits the performance information to the customer terminalC1 using an Internet communication protocol upon request from thecustomer terminal C1 requesting the display of the information. Herein,each of the customers who purchased the plasma chambers receives a“browsing password” for viewing the performance information before theplasma processing apparatus is delivered to the customer from themaintenance engineer. The password is required when the customer wishesto view operation and maintenance information which is part of theperformance information, and the server S sends the operation andmaintenance information to the customer terminal C1 only when aregistered browsing password is provided.

The above-described “performance information”, details of which will bedescribed in a later section, comprises information regarding models ofthe plasma processing chambers of the plasma processing apparatus orplasma processing system available from the maintenance engineer,information regarding quality and performance of each model in the formof specifications, information regarding parameters indicative ofquality and performance of specific apparatuses delivered to customers,and information regarding parameters and maintenance history.

The information regarding quality and performance of specificapparatuses and the information regarding parameters and maintenancehistory are accessible only from the customers provided with “browsingpasswords”.

The performance information described above is provided in the form of“operation and maintenance information” and “standard performanceinformation”. The operation and maintenance information is a type ofinformation provided from the maintenance engineer or the customer tothe server S to indicate the actual state of operation and maintenance.The standard performance information is stored in the database D andserves as a catalog accessible from potential customers. The “standardperformance information” is an objective description regarding theperformance of the plasma processing performed in the plasma chamber andallows prediction of the deposition state when applied to depositionprocesses such as plasma-enhanced CVD and sputtering processes.

In this embodiment, the “standard performance information” is stored inthe database D.

Upon the request from the customer terminal C1 to view the “performanceinformation”, the server S retrieves the requested “standard performanceinformation” from the database D and sends the information to thecustomer terminal C1 of the customer in the form of a performanceinformation page. When a customer sends a request to view the“performance information” along with the browsing password of thecustomer, the server S retrieves the requested “standard performanceinformation” from the database D as described above, composes the“performance information” by combining the retrieved “standardperformance information” and the “operation and maintenance information”provided from the maintenance engineer through the engineer terminal C2,and sends the “performance information page” to the customer terminal C1of the customer.

The database D stores the “standard performance information”, which ispart of the “performance information”, according to the models of theplasma chambers of the plasma processing apparatus or plasma processingsystem, reads out the “standard performance information” in response toa search request sent from the server S, and transmits the retrievedinformation to the server S. Although only one server S is illustratedin FIG. 20, a plurality of servers are provided in this embodiment. Inthis respect, it is useful to store general purpose “standardperformance information” in the database D instead of these servers inorder for the information to be shared among the plurality of serversmanaged by maintenance engineers from different locations.

Next, an operation of the performance validation system for the plasmaprocessing apparatus or the plasma processing system having theabove-described structure will be explained in detail with reference tothe flowchart shown in FIG. 21. The flowchart illustrates the process ofproviding the “performance information” executed at the server S.

Generally, the maintenance engineer presents, as a reference forpurchase, the “standard performance information” contained in the“performance information” of a model of the plasma chamber themaintenance engineer is attempting to sell to the customer. The customeris able to understand the performance of the plasma chamber and possibleplasma processes using the plasma chamber through this “standardperformance information”.

The customer who purchased the plasma processing apparatus of the plasmaprocessing system are provided with the “standard operationinformation”, which serves as the reference during the use of the plasmachambers, and the “operation and maintenance information”, which servesas the parameters of the operation. The customer, i.e., the user of theplasma chambers, may validate the operation of the plasma chambers bycomparing the “standard performance information” and the “operation andmaintenance information” so as to be informed of the state of the plasmaprocessing and to determine whether it is necessary to performmaintenance.

For example, a customer who is considering purchasing a new plasmachamber from the maintenance engineer may access the server S to easilyconfirm the “standard performance information” of the plasma chamber thecustomer is intending to purchase as follows.

The customer who desires to view the “performance information” firstsends from the customer terminal C1 a request for access to the server Sbased on an IP address of the server S set in advance.

Upon receiving the request for access (Step S1), the server S transfersa main page CP to the customer terminal C1 (Step S2).

FIG. 22 shows an example of the main page CP sent from the server S tothe customer terminal C1 through the steps described above. The mainpage CP comprises model selection buttons K1 to K4 for displaying the“standard performance information” contained in the “performanceinformation” according to models available from the maintenance engineerand a user button K5 for requesting the display of a customer pageexclusive to the customer to whom the maintenance engineer delivered theplasma processing chamber.

For example, a customer may select one of the model selection buttons K1to K4 using a pointing device (for example, a mouse) of the customerterminal C1 so as to specify which model of the plasma chamber thecustomer desires to obtain the information about. Such a selection isregarded as the request for accessing the “standard performanceinformation” among the “performance information”, and a request to thateffect is sent to the server S.

Upon receipt of the request (Step S3), the server S sends the customerterminal C1 a subpage containing the requested information on theselected model. That is, when display of “standard performanceinformation” is requested by specifying a model (A in FIG. 21), theserver S retrieves data such as “vacuum performance”, “gascharge/discharge performance”, “temperature performance”, “electricalperformance of the plasma processing chamber”, and the like, and dataregarding variations in these parameters effected in the plasmaprocessing apparatus or plasma processing system from the database D andsends the customer terminal C1 a specifications page CP1 shown in FIG.23 containing these data (Step S4).

As shown in FIG. 23, the specifications page CP1 comprises an apparatusmodel section K6 indicating the selected model of the apparatus, avacuum performance section K7, a gas charge/discharge performancesection K8, a temperature performance section K9, and an electricalperformance section K10 indicating the electrical performance of theplasma processing chamber. These constitute the “standard performanceinformation” of the selected model and each contains the followingdescriptions.

The vacuum performance section K7 contains below:

-   -   ultimate degree of vacuum: 1×10⁻⁴ Pa or less; and    -   operational pressure: 30 to 300 Pa.

The gas supply/discharge performance section K8 contains below:

-   -   maximum gas flow rates:        -   SiH₄ 100 SCCM,        -   NH₃ 500 SCCM,        -   N₂ 2,000 SCCM; and    -   discharge property: 20 Pa or less at a flow of 500 SCCM.

The temperature performance section K9 contains below:

-   -   heater temperature: 200 to 350 ±10° C.; and    -   chamber temperature: 60 to 80 ±2.0° C.

Herein, the SCCM (standard cubic centimeters per minute) valuesrepresent the corrected gas flow rates at standard conditions (0° C. and1,013 hPa) and the unit thereof is cm³/min.

A variation in each of the above-described parameters P among theplurality of the plasma chambers constituting the plasma processingapparatus or the plasma processing system is defined by relationship(10B) below:.(P_(max)−P_(min))/(P_(max)+P_(min))  (10B)wherein P_(max) represents the maximum value of a particular parameteramong the plurality of the plasma processing chambers and P_(min)represents the minimum value of the particular parameter among theplurality of the plasma processing chambers. The upper limit of thevariation in the plasma processing apparatus or system is displayed foreach of the parameters.

In the electrical performance section K10, the following items areincluded: a value of the plasma electrode capacitance C_(e) between theplasma excitation electrode 4 and the susceptor electrode 8 of theplasma processing apparatuses described in the first, second, ninth, andtenth embodiments and the plasma processing system of the eleventhembodiment; a value of the loss capacitance C_(X) between the plasmaexcitation electrode 4 and the ground potential positions; the settingranges of these capacitances; and relationship between C_(X) and C_(e).In addition to these, values of resonant frequency f, impedance Z at apower frequency, resistance R of the plasma processing chamber, andreactance X are included in the electrical performance section K10. Asthe resonant frequency f, a first series resonant frequency f₀ of theplasma processing chamber or a series resonant frequency may be used.Here, the first series resonant frequency f₀ is measured at an input endof the radiofrequency feeder, and the series resonant frequency isdefined by the capacitance between the electrode and the counterelectrode. The electrical performance section K10 further includes thesetting range of the first series resonant frequency f₀ and therelationship between the first series resonant frequency f₀ and thepower frequency f_(e).

Furthermore, the specification page CP1 includes a performance guaranteestatement such as “we guarantee that each of the parameters is withinthe setting range described in this page upon the delivery of the plasmachamber”.

In this manner, the overall radiofrequency electrical characteristics ofthe plasma chamber and the variation in the electrical characteristicsof the plasma chambers can be presented to a potential purchaser as anovel reference which has never been considered before. The performanceinformation can be printed out at the customer terminal C1 or theengineer terminal C2 to make a hard copy thereof so that the informationcan be presented in the form of a catalog or specifications describingthe performance information containing the above-described detailedinformation. When settings of the first series resonant frequency f₀,the resistance R, the reactance X, the plasma electrode capacitanceC_(e), the loss capacitance C_(x), and the like, and the performanceguarantee statement are presented to a potential purchaser through aterminal such as customer terminal C1, through a catalog, or through aspecification, the potential purchaser may judge the performance of theplasma chamber just as if the customer is examining electricalcomponents and may then purchase the plasma chamber from the maintenanceengineer based on that judgement.

After the server S completes the transmission of the above-describedsubpage to the customer terminal C1, the server S waits for the requestto display another subpage (Step S3) if a log-off request from thecustomer terminal C1 is not received (Step S5). If a log-off requestfrom the customer terminal C1 is received by the server S (Step S5), theserver S terminates the interaction with the customer terminal C1.

The customer who purchased and obtained the plasma chamber from themaintenance engineer can easily check the “performance information” ofthe specific plasma chambers of the plasma processing apparatus orsystem that the customer purchased, by accessing the server S as below.

When the customer and the maintenance engineer enter a sales contract, acustomer ID, which is unique to the individual customer and a “customerpassword (browsing password)” for accessing the “operation andmaintenance information” of the plasma processing apparatus or system orthe plasma chambers thereof are given to the individual customer by themaintenance engineer. The customer ID may be associated with the serialnumber of the purchased plasma processing apparatus or system or withthe serial number of the plasma chambers constituting the plasmaprocessing apparatus or system. The server S sends the “operation andmaintenance information” to the customer terminal C1 only when theregistered browsing password is provided.

A customer who desires to access the information selects the user buttonK5 in the above-described main page CP to send the request for thedisplay of a customer page to the server S.

Upon receiving the request for the display (Step S3-B), the server Ssends a subpage prompting the customer to input the “browsing password”(Step S6). FIG. 24 is an illustration of a customer page CP2. Thecustomer page CP2 comprises a customer ID input field K11 and a passwordinput field K12.

The customer page CP2 prompting the customer to input is displayed atthe customer terminal C1. In response to the prompt, the customer entersthe “browsing password” and the “customer ID”, which are provided fromthe maintenance engineer, through the customer terminal C1 so as toallow the server S to identify the plasma processing apparatus or systemand the plasma chambers thereof that the customer has purchased.

At this stage, the customer enters the customer ID into the customer IDinput field K11 shown in FIG. 24 and the browsing password into thepassword input field K12 shown in FIG. 24. The server S sends the“operation and maintenance information” subpage previously associatedwith that “browsing password” to the customer terminal C1 (Step S9),only when the server S receives the registered “customer ID” and the“browsing password” from the customer terminal C1 (Step S7).

In other words, the “operation and maintenance information” isaccessible only by the specific customer who entered the sales contractfor that plasma processing apparatus or system, i.e., who is inpossession of the registered “browsing password”. A third party usingthe server S cannot access the “operation and maintenance information”.Although the maintenance engineer often exchanges sales contracts with aplurality of customers simultaneously and delivers a plurality of plasmachambers for these customers simultaneously, each of the customers isprovided with a “browsing password” unique to the customer, unique tothe plasma processing apparatus or system, or unique to each one of theplasma chambers constituting the plasma processing apparatus or systemand is capable of individually accessing the “operation and maintenanceinformation” associated with the “browsing password” assigned to thatcustomer.

Thus, it becomes possible to securely prevent confidential informationregarding the purchase of the plasma chamber from leaking to othercustomers. Furthermore, the plasma processing apparatus, the plasmaprocessing system, the plasma processing chambers thereof can beseparately identified even when they are delivered simultaneously.

If the server S does not receive a registered “browsing password” (StepS7), a message refusing the access and prompting the customer to reenterthe “browsing password” is sent to the customer terminal C1 (Step S8).If the customer erroneously entered the “browsing password”, thecustomer may take this opportunity to reenter a correct password toaccess the “operation and maintenance information”.

When the ID and the password are verified (Step S7), the server Sretrieves data corresponding to the requested information from thedatabase D and sends it to the customer terminal C1 in the form of asubpage. That is, when the server S receives a request from the customerterminal C1 requesting display of the “standard performance information”and the “operation and maintenance information” of the specific plasmaprocessing apparatus or system and the plasma processing chambersthereof identified by the customer ID, data such as “vacuumperformance”, “gas charge/discharge performance”, “electricalperformance of the plasma processing chamber”, and the like areretrieved from the database D by specifying the apparatus model, and aspecification page (subpage) CP3 containing these data is sent to thecustomer terminal C1 (Step S9).

FIG. 25 is an illustration of a maintenance history page (subpage) CP3containing “operation and maintenance information”, which is sent fromthe server S to the customer terminal C1. As shown in FIG. 25, themaintenance history page CP3 comprises a serial number section K13indicating the serial numbers of the plasma processing apparatus orsystem and the plasma processing chambers thereof, the vacuumperformance section K7, the gas charge/discharge performance section K8,the temperature performance section K9, the electrical performancesection K10, a vacuum performance maintenance section K14, a gascharge/discharge performance maintenance section K15, a temperatureperformance maintenance section K16, and an electrical propertymaintenance section K17. These sections from K14 to K17 constitute the“operation and maintenance information” of the specific plasma chamberthat is purchased.

An example of the description contained in the vacuum performancemaintenance section K14 is as follows:

-   -   ultimate degree of vacuum: 1.3×10⁻⁵ Pa or less;    -   operational pressure: 200 Pa.

An example of the description contained in the gas charge/dischargeperformance maintenance section K15 is as follows:

-   -   gas flow rates:        -   SiH₄ 40 SCCM,        -   NH₃ 160 SCCM,        -   N₂ 600 SCCM; and    -   discharge property: 6.8×10⁻⁷ Pa·m³/sec.

An example of the description contained in the temperature performancemaintenance section K16 is as follows:

heater temperature: 302.3 ±4.9° C.; and

chamber temperature: 80.1 ±2.1° C.

The variation in each of the above-described parameters P among theplurality of plasma processing chambers constituting the plasmaprocessing apparatus or the plasma processing system is defined byrelationship (10B) below:(P_(max)−P_(min))/(P_(max)+P_(min))  (10B)wherein P_(max) represents the maximum value of a particular parameteramong the plurality of the plasma processing chambers and P_(min)represents the minimum value of the particular parameter among theplurality of the plasma processing chambers. The variation is calculatedas above using the measured values and is displayed for each of theparameters P.

A “detail” button K18 is provided in each of the sections K14, K15, K16,and K17. The customer may access the detailed information of the desiredsection by selecting one of the “detail” buttons K18 provided in thedesired section.

When the customer submits a display request by selecting the “detail”button K18, a detailed maintenance page CP4 including detailedinformation on the maintenance history is transmitted from the server Sto the customer terminal C1.

FIG. 26 shows the detailed maintenance page CP4 (subpage) of theelectrical performance section K10 transmitted from the server S to thecustomer terminal C1.

As shown in FIG. 26, the detailed maintenance page CP4 comprises theserial number display sections K13 for displaying the serial numbers ofthe purchased plasma processing apparatus or system and the plasmachambers thereof, the electrical performance section K10, and theelectrical property maintenance section K17. In the electrical propertymaintenance section K17, the values of the parameters P measured at thetime of maintenance and the values of the variation among these measuredvalues of the parameters P are displayed according to the serial numbersof the plasma processing chambers constituting the plasma processingapparatus or system.

The electrical property maintenance section K17 includes measured valuesof the plasma electrode capacitance C_(e) between the plasma excitationelectrode 4 and the susceptor electrode 8 and the loss capacitance C_(X)between the plasma excitation electrode 4 and ground potential positionswhich are DC-grounded, the setting ranges of these capacitances, and therelationship between C_(e) and C_(X) described in relation with theplasma processing apparatus of the first, second, ninth and tenthembodiments and the plasma processing system of the eleventh embodiment.In addition to these, the measured values of the resistance R andreactance X of the plasma processing chamber at the power frequencyf_(e) and the first series resonant frequency f₀, the setting range ofthe first series resonant frequency f₀, and the relationship between thefirst series resonant frequency f₀ and the power frequency f_(e) areincluded in K17.

As shown in FIGS. 25 and 26, in both the maintenance history page CP3and the detailed maintenance page CP4, the “operation and maintenanceinformation” and the “standard performance information” comprising datasuch as the “vacuum performance”, “gas charge/discharge performance”,“temperature performance”, “electrical performance”, etc. retrieved fromthe database D, are displayed together. Thus, the customer can view the“operation and maintenance information” while referring to the “standardperformance information”. The customer may use the “standard performanceinformation” as the reference during use and the “operation andmaintenance information” as the parameter indicative of the actual stateof the operation. By comparing the “standard performance information” tothe “operation and maintenance information”, the customer can validatethe operation of the plasma processing apparatus or system and theplasma processing chambers thereof, determine whether it is necessary toperform maintenance, and be informed of the state of the plasmaprocessing.

If the server S does not receive a log-off request from the customerterminal C1 after transmission of the subpages CP3 and CP4 to thecustomer terminal C1 (Step S5), the server S transmits an invalidconnection message to the customer terminal C1 (Step S8) to promptreentry of the “customer password” or to wait for the next displayrequest (Step S3). If the server S receives the log-off request from thecustomer terminal C1 (Step S5), the communication with the customerterminal C1 is terminated.

The performance validation system for a plasma processing apparatus orsystem according to this embodiment comprises a customer terminal, anengineer terminal, and an information providing means. The customer mayrequest via a public line access to the performance informationindicative of the operational performance of the plasma processingapparatus or system the customer purchased from the engineer. Theengineer uploads to the information providing means the performanceinformation through the engineer terminal. The information providingmeans provides the customer terminal with the performance informationuploaded through the engineers terminal. The performance informationincludes the loss capacitance C_(X) and a variation in the losscapacitance C_(X) among the plasma processing chambers constituting theplasma processing apparatus or system and can be output as a catalog orspecifications document. Thus, the performance information including theperformance standard information and operation and maintenanceinformation of the plasma processing chambers constituting the plasmaprocessing apparatus and system is accessible for the customer viapublic lines as a basis for making a purchasing decisions at the time ofpurchase or as a reference for evaluating the performance of the plasmaprocessing chambers during the use of the plasma processing apparatusand system.

Moreover, because the performance information includes the informationregarding the loss capacitance C_(X), a variation of the C_(X), theplasma electrode capacitance C_(e), and a variation of C_(e), the basisfor determining the operation of the plasma processing chambers of theplasma processing apparatus or system purchased by the customer can bereadily provided to the customer. For the customer considering ofpurchasing a new plasma processing apparatus, the information serves asa basis for making purchasing decisions. The performance information canbe output as a catalog or a specification document.

The validation system of this embodiment can be applied to a plasmaprocessing apparatus of any type, for example, a plasma processingapparatus of the first or second embodiments described above, a plasmaprocessing apparatuses of ninth or tenth embodiment described below, anda plasma processing system of eleventh embodiment described below.

Seventh Embodiment

A performance evaluation method of the plasma processing apparatusaccording to a seventh embodiment of the present invention will now bedescribed with reference to the drawings.

In the performance evaluation method of this embodiment, the plasmaprocessing apparatus according to the first embodiment shown in FIGS. 1to 8 is evaluated.

This performance evaluation method determines that the plasma processingapparatus maintains a required level of performance when a losscapacitance C_(X1) of the plasma processing chamber after the deliveryis less than 26 times the plasma electrode capacitance C_(e1) and thatthe plasma processing apparatus does not maintain the required level ofperformance when the loss capacitance C_(X1) is not less than 26 timesthe plasma electrode loss capacitance C_(e1), wherein the losscapacitance C_(X1) is measured between the plasma excitation electrodeand ground potential positions which are DC-grounded and the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode 4 and the counter electrode 8 which generate a plasma incooperation with each other. When the required level of performance isnot maintained, a corrective action for correcting the loss capacitanceC_(X1) is performed such that the loss capacitance C_(X1) is less than26 times the plasma electrode capacitance C_(e1).

The loss capacitance C_(X) may be corrected, for example, according tomethods (1) to (7) described in the first embodiment.

In this performance evaluation method, the above corrective action canbe readily performed; hence, the overall radiofrequency characteristicsof the plasma processing apparatus 75 can be readily optimized.

As a result, electrical power from the radiofrequency generator 1 can beeffectively fed into the plasma space between the plasma excitationelectrode 4 and the susceptor electrode 8 even if the inputradiofrequency is higher than 13.56 MHz, which is conventionally used.If the same frequency is supplied, the electrical power will be moreefficiently consumed in the plasma space of each plasma processingchamber compared with conventional plasma processing apparatuses. As aresult, the processing rate is improved by the higher-frequency plasmaexcitation. In other words, the deposition rate of the layer is improvedin the plasma enhanced CVD or the like.

Since an adequate corrective action is performed based on the results ofthe performance evaluation method according to this embodiment, inputpower is effectively supplied into the plasma space, thus preventingundesirable spreading of the plasma. Moreover, uniform plasma treatmentis achieved on the substrate 16. When a film is deposited on thesubstrate 16, the thickness of the film is uniform.

Moreover, feeding of higher radiofrequency enables the plasma potentialto reduce, avoiding damage by ions. Thus, the layer quality is improvedin layer deposition treatments such as plasma enhanced CVD andsputtering. That is, the higher-wave radiofrequency contributes toimprovements in isolation voltage, etching resistance in etchingsolutions, and density or hardness of the resulting layer. The layerdensity is represented by, for example, etching resistance in a BHFsolution.

After the above corrective action, electrical power with a certainfrequency will be more effectively supplied to the plasma space comparedwith conventional plasma processing apparatus, improving electricalconsumption efficiency. Thus, a desired deposition rate and a desiredlayer property are achieved by reduced power input, resulting in reducedoperation costs. Moreover, the processing time is reduced, thusimproving productivity and contributing to carbon dioxide emissionreduction due to reduced electrical power consumption.

According to the performance evaluation method of this embodiment, theloss capacitance C_(X) is measured with the RF characteristic meter ANat the installation site of the plasma processing apparatus. Theperformance of the plasma processing apparatus can be thereby checkedand evaluated within a short time. Since no substrate with depositedlayers is used for checking, the performance validation and evaluationof the plasma processing apparatus does not require shutdown of theproduction line for several days to several weeks, thereby improvingproductivity of the production line.

Since the loss capacitance C_(X) mainly depends on the mechanicalstructure, thus individual plasma processing chambers have differentloss capacitances. By setting these loss capacitances to theabove-described range, the overall radiofrequency characteristics ofthese plasma chambers can be optimized, achieving stable plasmageneration. Consequently, the plasma processing apparatus exhibitsimproved operation stability.

Because the performance evaluation is performed after the apparatus isdisassembled at the engineer site, is transferred to the customer site,and is reassembled at the customer site, the performance of theapparatus can be readily checked for a short time in view of factorswhich adversely affect the performance, such as misalignment due tovibration during transfer and unsatisfactory reassembling. Moreover, aperiod from finding to solving the problem can be reduced; hence, theapparatus can be readily used in practice after a reduced amount ofinstallation and set-up time.

Eighth Embodiment

A performance evaluation method for the plasma processing apparatusshown in the second embodiment with reference to FIGS. 11 to 14 will nowbe described.

This performance evaluation method determines that the plasma processingapparatus maintains a required level of performance when a losscapacitance C_(X1) of the plasma processing chamber after the deliveryis less than 26 times the plasma electrode capacitance C_(e1) and thatthe plasma processing apparatus does not maintain the required level ofperformance when the loss capacitance C_(X1) is not less than 26 timesthe plasma electrode loss capacitance C_(e1), wherein the losscapacitance C_(X1) is measured between the plasma excitation electrodeand ground potential positions which are DC-grounded and the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode 4 and the counter electrode 8 which generate a plasma incooperation with each other, as in the second embodiment. When therequired level of performance is not maintained, a corrective action forcorrecting the loss capacitance C_(X1) is performed such that the losscapacitance C_(X1) is less than 26 times the plasma electrodecapacitance C_(e1).

The loss capacitance C_(X) may be corrected, for example, according tomethods (1) to (7) described in the second embodiment.

The performance evaluation method according to the eighth-embodimentevaluates whether or not 5 times the plasma electrode capacitance C_(e)″during the plasma emission mode (5×d/δ times the plasma electrodecapacitance C_(e) between the plasma excitation electrode 4 and thecounter electrode 8) is larger than the loss capacitance C_(X) definedas above.

The performance evaluation method for the plasma processing apparatus ofthis embodiment has substantially the same advantages as those in theseventh embodiment. Moreover, the detachable RF characteristic meter ANis connected to the impedance measuring terminal 61 and the switches SW1and SW2 having impedances Z₁ and Z₂, respectively, which are equal toeach other, are provided. Thus, the radiofrequency characteristics suchas the plasma electrode capacitance C_(e) and the loss capacitance C_(X)can be determined only by changing the switches SW1 and SW2 withoutdetaching the plasma processing chamber from the matching circuit 2A.

Moreover, 5×d/δ times the actual interelectrode capacitance C_(e) iscompared with the loss capacitance C_(X) to evaluate the radiofrequencycharacteristics of the parallel plate electrodes 4 and 8. Thus, electricpower can be more effectively supplied into the plasma emission space,and the power consumption and plasma processing are optimized.

Ninth Embodiment

FIG. 27 is a schematic view of a plasma processing apparatus 71 which isused in the performance evaluation method in accordance with thisembodiment.

This plasma processing apparatus 71 has a plurality of processingchamber units which permit a consecutive treatment of, for example, fromthe deposition a polycrystalline silicon layer which functions as asemiconductor active layer to the deposition of the gate insulatinglayer in a top-gate TFT.

In the plasma processing apparatus 71, five processing chamber units,one loading chamber 73, and one unloading chamber 74 are continuouslyarranged around a substantially heptagonal transfer chamber 72. The fiveprocessing chamber units are a first deposition chamber 75 fordepositing an amorphous silicon layer, a second deposition chamber 76for depositing a silicon oxide layer, a third deposition chamber 77 fordepositing a silicon nitride layer, a laser annealing chamber 78 forannealing a processed substrate after deposition, and an annealingchamber 79 for performing a heat treatment of the processed substrate.

The first deposition chamber 75, the second deposition chamber 76, andthe third deposition chamber 77 have substantially the sameconfiguration as that of the dual-frequency plasma processing apparatusof the first embodiment shown in FIGS. 1 to 8 and may perform differenttreatments for forming different layers or the same treatment using thesame recipe.

The processing chambers 75, 76, and 77 have the same configuration asthat of the plasma processing apparatus described in the firstembodiment, and detailed description thereof is omitted.

In the deposition of the amorphous silicon layer, the silicon oxidelayer, and the silicon nitride layer in the processing chambers 75, 76,and 77, respectively, as shown in FIG. 1, a substrate 16 to be treatedis placed on a susceptor electrode 8. A radiofrequency voltage isapplied to both a plasma excitation electrode 4 and the susceptorelectrode 8 from a radiofrequency generator 1, while a reactive gas issupplied from a gas feeding tube 17 into a chamber space 60 through ashower plate 6 to generate a plasma. The target layer is thereby formedon the substrate 16.

Referring to FIG. 28, the laser annealing chamber 78 is provided with alaser light source 81 on the upper wall 80 and a stage 82 for placingthe substrate 16 on the bottom wall of the chamber. The stage 82 ishorizontally movable in the orthogonal X and Y directions. Spot laserlight 83 (shown by chain lines) is emitted from an aperture 81 a of alaser light source 81, while the stage 82 holding the substrate 16horizontally moves in the X and Y directions so that the laser light 83scans the entire surface of the substrate 16. Examples of the laserlight sources 81 are gas lasers using halogen gases, such as XeCl, ArF,ArCl, and XeF.

The laser annealing chamber 78 may have any configuration as long as thespot laser beam from the laser light source can scan the entire surfaceof the substrate to be treated. Also, in this case, gas lasers usinghalogen gases, such as XeCl, ArF, ArCl, and XeF can be used as laserlight sources. Alternatively, other laser light sources such as a YAGlaser may be used depending on the type of the layer to be annealed.Laser annealing may be pulsed laser annealing or continuouslyoscillating laser annealing. The annealing chamber may have aconfiguration of, for example, a multistage electrical furnace type.

Referring to FIG. 29, the annealing chamber 79 is of a multistageelectrical furnace type. In the annealing chamber 79, a plurality ofsubstrates 16 is placed on heaters 85 which are vertically arranged inthe chamber. These heaters 85 are energized to heat the substrates 16. Agate valve 86 is provided between the annealing chamber 79 and thetransfer chamber 72.

Referring to FIG. 27, the loading chamber 73 and the unloading chamber74 are provided with a loading cassette and an unloading cassette,respectively, which are detachable from these chambers. These cassettescan contain a plurality of substrates 16, that is, the loading cassettecontains unprocessed substrates 16 whereas the unloading cassettecontains processed substrates 16. A transfer robot 87 for transferringthe substrates 16 is placed in the transfer chamber 72 which issurrounded by the processing chamber units, the loading chamber 73, andthe unloading chamber 74. The transfer robot 87 is provided with an arm88 thereon. The arm 88 has an expandable and shrinkable link mechanismand can rotate and vertically move. The substrate 16 is supported andtransferred by the end of the arm 88.

In this plasma processing apparatus 71, the operations of the processingchamber units are automatically controlled by a control section, whereasvarious processing conditions, such as layer deposition conditions,annealing conditions, and heating conditions, and process sequences arecontrolled by an operator. In the operation of the plasma processingapparatus 71, untreated substrates 16 are set on the loading cassette,and are transferred from the loading cassette into each processingchamber by the transfer robot 87 based on the starting operation by theoperator. After the substrates 16 are automatically and sequentiallyprocessed in each chamber, the substrates 16 are placed onto theunloading cassette by the transfer robot 87.

In the performance evaluation method for the plasma processing apparatus71 of this embodiment, a variation C_(x1r) in the loss capacitancesC_(X1) of these processing chambers 75, 76, and 77 after the delivery isdefined by the maximum C_(X1max) and the minimum C_(X1min) as follows:C _(X1r)=(C _(X1max) −C _(X1min))/(C _(X1max) +C _(X1min))The required level of performance is determined by whether or not thevariation C_(X1r) is less than 0.1. That is, the method determine thatrequired level of performance is maintained when the variation C_(X1r)is less than 0.1 and that the required level of performance is notmaintained when the variation C_(X1r) is 0.1 or more.

The definition, the measuring method, and the corrective action of theloss capacitance C_(X) are described in the first embodiment.

In addition to the evaluation of the variation C_(X1r), a variationC_(e1r) of the plasma electrode capacitances C_(e1) of these processingchambers 75, 76, and 77 after the delivery is defined by the maximumC_(e1max) and the minimum C_(e1min) as follows:C _(e1r)=(C _(e1max) −C _(e1min))/(C _(e1max) +C _(e1min))The required level of performance is determined by whether or not thevariation C_(e1r) is less than 0.1. That is, the method determine thatrequired level of performance is maintained when the variation C_(e1r)is less than 0.1 and that the required level of performance is notmaintained when the variation C_(e1r) is 0.1 or more.

This performance evaluation method facilitates corrective action fordifferences in radiofrequency characteristics between the processingchambers 75, 76, and 77. Since the loss capacitance C_(X) and the plasmaelectrode capacitance C_(e1) of these processing chambers 75, 76, and 77are controlled within a predetermined range, these processing chambers75, 76, and 77 consume substantially the same electrical power.

Accordingly, substantially the same result is achieved from a singleprocess recipe for these processing chambers 75, 76, and 77. When layersare formed in these processing chambers 75, 76, and 77, these layers canhave substantially the same characteristics, e.g., the thickness, theisolation voltage, and the etching rate. When the variation iscontrolled to be less than 0.1 under the same deposition conditions inthe plasma chambers 75, 76, and 77, the variation in layer thickness canbe controlled to be less than ±5%.

As a result, the overall radiofrequency characteristics of the plasmaprocessing apparatus 71 can be optimized so as to generate a stableplasma. Thus, the operations of the processing chambers 75, 76, and 77of the plasma processing apparatus 71 are stable and uniform. Such aperformance evaluation method has not been considered in conventionalprocesses.

The above-mentioned method does not require a determination of processconditions by the relationships between enormous amounts of data onthese processing chambers 75, 76, and 77 and the results obtained byevaluation of actually processed substrates.

Thus, in installation of new systems and inspection of installedsystems, the time required for obtaining substantially the same resultsusing the same process recipe in these processing chambers 75, 76, and77 can be significantly reduced by measuring the plasma electrodecapacitance C_(e) and the loss capacitance C_(X) compared with aninspection method by actual deposition onto the substrate 16. Moreover,according to this inspection method, the plasma processing apparatus 71can be directly evaluated in situ in a short period of time, instead ofa two-stage evaluation, i.e., processing of the substrates andconfirmation and evaluation of the operation of the plasma processingapparatus 71 based on the evaluation of the processed substrates. Inthis embodiment, inspection by layer deposition on substrates isperformed to determine the process recipe when the plasma processingapparatus is installed. Since the plasma processing chambers 75, 76, and77 have the same radiofrequency characteristics, the layer depositionmay be performed in only one of the chambers. In the maintenance of theplasma processing apparatus, actual layer deposition is not requiredbecause the radiofrequency characteristics of the plasma processingchambers are controlled within the predetermined value. In contrast, inconventional methods performing actual layer deposition on substrates,these plasma processing chambers must be independently evaluated.

Accordingly, the inspection method of this embodiment does not require ashutdown of the production line for several days to several weeks tocheck and evaluate the operation of the plasma processing apparatus 71.The production line, therefore, has high productivity with reducedexpenses for substrates used in the inspection, processing of thesesubstrates, and labor during the inspection operations.

The performance evaluation methods described in the seventh to eighthembodiments are also applicable to the processing chambers 75, 76, and77. By using both the evaluation based on the comparison of the losscapacitance C_(X) with the plasma electrode capacitance C_(e) of eachprocessing chamber and the evaluation based on the variation C_(X1r),the overall radiofrequency characteristics of the processing chambers75, 76, and 77, including a variation according to chambers, can bereadily optimized. These processing chambers 75, 76, and 77 therebyexhibit the same advantages as those in the seventh to ninthembodiments.

Tenth Embodiment

A performance evaluation method in accordance with a tenth embodiment ofthe present invention will now be described with reference to thedrawings.

FIG. 30 is a cross-sectional view of an outline configuration of aplasma processing apparatus 91 used in this embodiment. The plasmaprocessing apparatus 91 has a load-lock chamber 93, an annealing chamber99, and processing chambers 95 and 96 which are provided around asubstantially square transfer chamber (waiting chamber) 92. The transferchamber 92 contains a transfer robot for transferring substrates and hasgates g1, g2, g3, and g4 at the interfaces to the chambers. The transferchamber 92, the heating chamber 99, and the processing chambers 95 and96 are evacuated to high vacuum by individual high-vacuum pumps. Theload-lock chamber 93 is evacuated to low vacuum by a low-vacuum pump.

The components of the plasma processing apparatus 91 of this embodimentcorrespond to those of the plasma processing apparatus 75 of the firstembodiment shown in FIGS. 1 to 8 and the plasma processing apparatus 71of the ninth embodiment shown in FIG. 27 to 29. That is, the transferchamber 92 corresponds to the transfer chamber 72, the annealing chamber99 corresponds to the annealing chamber 79, and the load-lock chamber 93corresponds to the loading chamber 73 and the unloading chamber 74. Thecomponents having the same configurations are not described.

In this plasma processing apparatus 91, a gate g0 is opened to transferthe substrate 16 into the load-lock chamber 93. The gate g0 is closed toevacuate the load-lock chamber 93 by a low-vacuum pump. The gates g1 andg2 are opened to transfer the substrate 16 from the load-lock chamber 93to the heating chamber 99 by a transfer arm of a transfer robot in thetransfer chamber 92. The gates g1 and g2 are closed to evacuate thetransfer chamber 92 and the heating chamber 99 using a high-vacuum pump.After the substrate 16 is annealed, the gates g2 and g4 are opened totransfer the annealed substrate 16 to the processing chamber 95 by thetransfer arm of the transfer robot. After the substrate 16 is processedin the processing chamber 95, the gates g3 and g4 are opened to transferthe substrate 16 to the plasma chamber 96 by the transfer arm of thetransfer robot in the transfer chamber 92. After the substrate 16 isprocessed in the plasma chamber 96, the gates g1 and g3 are opened totransfer the substrate 16 to the load-lock chamber 93 by the transferarm of the transfer robot in the transfer chamber 92.

Individual sections are automatically operated by a controller section,although the processing conditions such as layer deposition conditionsin these processing chambers and the processing sequence are set by anoperator. In the use of this plasma processing apparatus 91, anuntreated substrate 16 is placed onto a loading cassette in theload-lock chamber 93 and the operator pushes a start switch. Thesubstrate 16 is sequentially transferred from the loading cassette toprocessing chambers by the transfer robot. After a series of processingsteps are sequentially performed in these processing chambers, thesubstrate 16 is placed into the unloading (loading) cassette by thetransfer robot.

In these processing chambers 95 and 96, as in the second embodiment, thesubstrate 16 is placed on the susceptor electrode 8, and theradiofrequency generator 1 supplies a radiofrequency power to the plasmaexcitation electrode 4 and the radiofrequency generator 27 suppliesanother radiofrequency power to the susceptor electrode 8, while areactive gas is fed into the plasma chamber 60 from the gas feeding tube17 via the shower plate 6 to generate a plasma for forming an amorphoussilicon layer, a silicon oxide layer, or a silicon nitride layer on thesubstrate 16.

These plasma processing chambers 95 and 96 are connected to a RFcharacteristic meter AN by switches SW2, as shown in FIG. 30. Avariation C_(e1r) in the plasma electrode capacitances C_(e1) of theseplasma processing chambers 95 and 96 after the delivery is defined bythe maximum C_(e1max) and the minimum C_(e1min) as follows:C _(e1r)=(C _(e1max) −C _(e1min))/(C _(e1max) +C _(e1min))The required level of performance is determined by whether or not thevariation C_(e1r) is less than 0.03. That is, the method determine thatrequired level of performance is maintained when the variation C_(e1r)is less than 0.03 and that the required level of performance is notmaintained when the variation C_(e1r) is 0.03 or more.

Also, a variation C_(X1r) in the loss capacitances C_(X1) of theseplasma processing chambers 95 and 96 after the delivery is defined bythe maximum C_(X1max) and the minimum C_(X1min) as follows:C _(X1r)=(C_(X1max) −C _(X1min))/(C _(X1max) +C _(X1min))The required level of performance is determined by whether or not thevariation C_(X1r) is less than 0.03. That is, the method determine thatrequired level of performance is maintained when the variation C_(X1r)is less than 0.03 and that the required level of performance is notmaintained when the variation C_(X1r) is 0.03 or more.

The performance evaluation method of this embodiment exhibits the sameadvantages as those in the ninth embodiment. Moreover, adequatecorrective action is performed to these plasma processing chambers 95and 96 based on the evaluation of the variation C_(e1r) in the plasmaelectrode capacitances C_(e1) after the delivery. Also, adequatecorrective action is performed to these plasma processing chambers 95and 96 based on the evaluation of the variation C_(X1r) in the losscapacitances C_(X1) after the delivery. Thus, the plasma processingchambers 95 and 96 have substantially the same radiofrequencycharacteristics, namely, the plasma electrode capacitance C_(e) and theloss capacitance C_(X). Since the plasma electrode capacitances C_(e)and the loss capacitances C_(X) of these processing chambers 95 and 96are controlled within a predetermined range, these processing chambers95 and 96 consume substantially the same electrical power.

Accordingly, substantially the same result is achieved from a singleprocess recipe for these different processing chambers 95 and 96. Whenlayers are formed in these plasma processing chambers 95 and 96, theselayers can have substantially the same characteristics, e.g., thethickness, the isolation voltage, and the etching rate. When thevariation is controlled to be less than 0.03 under the same depositionconditions in the plasma chambers 95 and 96, the variation in layerthickness can be controlled to be less than ±2%.

With reference to FIG. 7, in the plasma processing apparatus 91 of thisembodiment, the impedance measuring terminal 61 is provided at the inputend PR of the feed plate 3 in each of the processing chambers 95 and 96,and the RF characteristic meter AN is detachably connected to theimpedance measuring terminal 61. Moreover, the matching circuit 2A isdisconnected from the processing chambers 95 and 96 by operating theswitches SW1 and SW2 (FIG. 11) when the impedance characteristics of theprocessing chambers 95 and 96 are measured, as in the second embodiment.Thus, the loss capacitance C_(X) of the processing chambers 95 and 96can be readily measured without disconnecting the matching circuit 2Afrom the power supply line.

As described in the second embodiment, the impedance Z₁ is also equal tothe impedance Z₂ in these plasma processing chambers 95 and 96 in thisembodiment; hence, switching between the measuring mode of the losscapacitance C_(X) and the operating mode of the plasma processingapparatus can be readily performed only by operating the switches SW1and SW2, without connecting and disconnecting the matching circuit 2Aand a probe 105 for measuring the impedance shown in FIG. 9. Thus, themeasurements of the loss capacitances C_(X) of these processing chambers95 and 96 can be efficiently performed, by operating the switches SW1and SW2.

Since an adequate corrective action is performed for these plasmaprocessing chambers 95 and 96 based on the results of the performanceevaluation method according to this embodiment, the radiofrequencycharacteristics of the parallel plate electrodes 4 and 8 can be directlydefined. Thus, input power is effectively supplied into the plasmaspace, resulting in further improved electrical power consumption andimproved processing efficiency in the overall plasma processingapparatus 91.

In this embodiment, the two switches SW1 and SW2 are provided. Since theessential feature in this embodiment is that the impedance from thebranch to the measuring point PR is equal to the impedance from thebranch to the probe, this requirement may be satisfied using one switch.

The performance evaluation methods described in the seventh to ninthembodiments are also applicable to the processing chambers 95 and 96. Byusing both the evaluation based on the comparison of loss capacitanceC_(X) with 26 times the plasma electrode capacitance C_(e) and theabove-mentioned evaluation based on the variations C_(X1r) and C_(e1r),the overall radiofrequency characteristics of the processing chambersprocessing chamber 95 and 96 can be simultaneously optimized. Theseprocessing chambers 95 and 96 thereby exhibit the same advantages asthose in the seventh to ninth embodiments.

Eleventh Embodiment

A performance evaluation method in accordance with an eleventhembodiment of the present invention will now be described with referenceto the drawings.

FIG. 31 is a schematic view of an outline configuration of a plasmaprocessing system used in the performance evaluation method of thisembodiment.

The plasma processing system of this embodiment is substantially acombination of plasma processing apparatuses 71 and 71′ which correspondto the plasma processing apparatus 71 shown in FIG. 27 (see the ninthembodiment) and a plasma processing apparatus 91 which corresponds tothe plasma processing apparatus 91 shown in FIG. 30 (see the tenthembodiment). Components having the same functions as in the ninth andtenth embodiments are referred to with the same reference numerals, anda detailed description thereof with reference to drawings has beenomitted.

As shown in FIG. 31, the plasma processing system of this embodimentconstitutes a part of a production line which includes the plasmaprocessing apparatus 71, the plasma processing apparatus 91, and theplasma processing apparatus 71′. The plasma processing apparatus 71 hasthree plasma processing chambers 95, 96, and 97. The plasma processingapparatus 91 has two plasma processing apparatuses 95 and 96. The plasmaprocessing apparatus 71′ has three plasma processing chambers 95, 96,and 97. These plasma processing chambers 95, 96, and 97 in the plasmaprocessing apparatuses 71, 71′, and 91 have substantially the sameconfiguration.

In the plasma processing system of the present invention, for example, asubstrate 16, which has been preliminarily treated, is subjected to afirst layer deposition treatment in the plasma processing apparatus 95of the plasma processing apparatus 71, is annealed in the annealingchamber 79, and is annealed in the laser annealing chamber 78. Thetreated substrate 16 is subjected to second and third layer depositiontreatments in the plasma processing chambers 96 and 97.

The substrate 16 is transferred from this plasma processing apparatus 71and a photoresist is applied thereto by a photolithographic step usinganother apparatus (not shown).

The substrate 16 is transferred into the plasma processing apparatus 91and is plasma-etched in the processing chambers 95 and 96. Next, thesubstrate 16 is transferred to another plasma processing chamber notshown in the drawing and is subjected to a layer deposition treatmenttherein.

The substrate 16 is transferred into the plasma processing apparatus 91and is plasma-etched in the processing chambers 95 and 96. Next, thesubstrate 16 is transferred to another plasma processing chamber notshown in the drawing and is subjected to a layer deposition treatmenttherein.

Finally, the substrate 16 is subjected to first, second, and thirddeposition treatments in the plasma processing chambers 95, 96, and 97of the plasma processing apparatus 71′, and is transferred to thesubsequent step to complete the steps in the plasma processing systemaccording to this embodiment.

Impedance measuring terminals of the plasma processing chambers 95, 96,and 97 are connected to an RF characteristic meter AN via a switch SW3.In the measurement of the impedance, the switch SW3 connects only one ofthe plasma chambers 95, 96, and 97 to the RF characteristic meter AN.Coaxial cables have the same length between the impedance measuringterminals of the plasma processing chambers 95, 96, and 97 and theswitch SW3 so that the impedances from these impedance measuringterminals to the switch SW3 are the same. A detachable probe of an RFcharacteristic meter AN is connected to the impedance measuringterminal, as in the third embodiment shown in FIG. 11.

The loss capacitance C_(X) of each plasma processing chamber 95, 96, or97 is measured by operating the switch SW3 as in the tenth embodiment.The variation C_(e1r) in the plasma electrode capacitances C_(e1) ofthese plasma processing chambers 95, 96, and 97 after the delivery isdefined by the maximum C_(e1max) and the minimum C_(e1min) as follows:C _(e1r)=(C _(e1max) −C _(e1min))/(C _(e1max) +C _(e1min))The required level of performance is determined by whether or not thevariation C_(e1r) is less than 0.03. That is, the method determine thatrequired level of performance is maintained when the variation C_(e1r)is less than 0.03 and that the required level of performance is notmaintained when the variation C_(e1r) is 0.03 or more.

Also, the variation C_(x1r) in the loss capacitances C_(X1) of theseplasma processing chambers 95, 96, and 97 after the delivery is definedby the maximum C_(X1max) and the minimum C_(X1min) as follows:C _(X1r)=(C _(X1max) −C _(X1min))/(C _(X1max) +C _(X1min))The required level of performance is determined by whether or not thevariation C_(X1r) is less than 0.03. That is, the method determine thatrequired level of performance is maintained when the variation C_(X1r)is less than 0.03 and that the required level of performance is notmaintained when the variation C_(X1r) is 0.03 or more.

The definition, the measuring method, and the corrective action of theloss capacitance C_(X) are described above.

The performance evaluation method of this embodiment exhibits the sameadvantages as those in the ninth and tenth embodiments. Moreover,adequate corrective action is performed to these plasma processingchambers 95, 96, and 97 based on the evaluation of the variation C_(e1r)in the plasma electrode capacitances C_(e1) after the delivery. Also,adequate corrective action is performed to these plasma processingchambers 95 and 96 based on the evaluation of the variation C_(X1r) inthe loss capacitances C_(X1) after the delivery. Thus, the plasmaprocessing chambers 95 and 96 have substantially the same radiofrequencycharacteristics, namely, the plasma electrode capacitance C_(e) and theloss capacitance C_(X). Since the plasma electrode capacitances C_(e)and the loss capacitances C_(X) of these processing chambers 95 and 96are controlled within a predetermined range, these processing chambers95, 96, and 97 consume substantially the same electrical power.

Accordingly, substantially the same result is achieved from a singleprocess recipe for these processing chambers 95, 96, and 97. When layersare formed in these processing chambers 95, 96, and 97, these layers canhave substantially the same characteristics, e.g., the thickness, theisolation voltage, and the etching rate. When the variation iscontrolled to be less than 0.03 under the same deposition conditions inthe plasma chambers 95, 96, and 97, the variation in layer thickness canbe controlled to be less than ±2%.

As a result, the overall radiofrequency characteristics of the plasmaprocessing system can be optimized so as to generate a stable plasma.Thus, the operations of the processing chambers 95, 96, and 97 of theplasma processing system are stable and uniform. Such a performanceevaluation method has not been considered in conventional processes.

The above-mentioned method does not require a determination of processconditions by the relationships between enormous amounts of data onthese processing chambers 95, 96, and 97 and the results obtained byevaluation of actually processed substrates.

Thus, in installation of new systems and inspection of installedsystems, the time required for obtaining substantially the same resultsusing the same process recipe in these processing chambers 95, 96, and97 can be significantly reduced by measuring the plasma electrodecapacitance C_(e) and the loss capacitance C_(X) compared with aninspection method by actual deposition onto the substrate 16. Moreover,according to this inspection method, the plasma processing system can bedirectly evaluated in situ in a short period of time, instead of atwo-stage evaluation, i.e., processing of the substrates andconfirmation and evaluation of the operation of the plasma processingsystem based on the evaluation of the processed substrates. In thisembodiment, inspection by layer deposition on substrates is performed todetermine the process recipe when the plasma processing system isinstalled. Since the plasma processing chambers 95, 96, and 97 have thesame radiofrequency characteristics, the layer deposition may beperformed in only one of the chambers. In the maintenance of the plasmaprocessing apparatus, actual layer deposition is not required becausethe radiofrequency characteristics of the plasma processing chambers arecontrolled within the predetermined value. In contrast, in conventionalmethods performing actual layer deposition on substrates, these plasmaprocessing chambers must be independently evaluated.

Accordingly, the performance evaluation method of this embodiment doesnot require a shutdown of the production line for several days toseveral weeks to check and evaluate the operation of the plasmaprocessing system. The production line, therefore, has high productivitywith reduced expenses for substrates used in the inspection, processingof these substrates, and labor during the inspection operations.

The performance evaluation methods described in the eighth to ninthembodiments are also applicable to the processing chambers 95, 96, and97. By using both the evaluation based on the comparison of losscapacitance C_(X) with 26 times the plasma electrode capacitance C_(e)and the above-mentioned evaluation based on the variations C_(X1r) andC_(e1r), the overall radiofrequency characteristics of the processingchambers processing chamber 95, 96, and 97 can be simultaneouslyoptimized. These processing chambers 95, 96 and 97 thereby exhibit thesame advantages as those in the eighth to ninth embodiments.

As described in the second embodiment, the impedance Z₁ is also equal tothe impedance Z₂ and the impedance from the interlayer 61 to the switchSW3 is identical in these plasma processing chambers 95, 96, and 97 inthis embodiment; hence, the measurements of the loss capacitances C_(X)of these processing chambers 95, 96, and 97 can be efficientlyperformed, by operating the switches SW1, SW2, and SW3.

In this embodiment, the operation of the switches SW1, SW2, and SW3 maybe cooperated with the switching of the plasma processing chambers 95,96, and 97. The switches SW1 and SW2 may be replaced with one switch inwhich the impedance from the branch point B to the output terminalposition PR is equal to that from the branch point B to the probe.

In the ninth to eleventh embodiments, as shown in FIG. 32, each of theplasma processing chambers 95, 96, and 97 is provided with a matchingcircuit 2A and a radiofrequency generator 1. An RF characteristic meterAN is connected to a connection point for every matching circuit 2A viaa switch SW4. Alternatively, as shown in FIG. 33, one radiofrequencygenerator 1 may be connected to three matching circuits 2A for theplasma processing chambers 95, 96, and 97, or as shown in FIG. 34, onematching circuit 2A may be connected to these plasma processing chambers95, 96, and 97. In such a case, the RF characteristic meter AN isconnected to a connection point between each plasma chamber and thematching circuit 2A via the switch SW4.

In the tenth and eleventh embodiment, a combination of the evaluationbased on the equationsC_(X1r)=(C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)) andC_(e1r)=(C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)) is described.Alternatively, the evaluation may be performed based only on theequation C_(X1r)=(C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)).

Twelfth Embodiment

A performance management system for a plasma processing apparatusaccording to a twelfth embodiment of the present invention will now bedescribed with reference to the drawings.

The configuration of the performance management system for the plasmaprocessing apparatus of this embodiment is identical to that of thethird embodiment shown in FIGS. 15 and 17. FIG. 35 is a flowchartshowing steps for providing evaluation information executed at theperformance management system for the plasma processing apparatus ofthis embodiment.

The performance management system shown in FIG. 17 includes all elementsof the system shown in FIG. 15 and a radiofrequency characteristic meter(capacitance meter) 260 connected to a plasma processing apparatus 250.No limit is imposed as to the types of the plasma processing apparatusfor which this performance management system is used. For example, theperformance management system can be applied to any one of the plasmaprocessing apparatuses according to the first, second, ninth, and tenthembodiments, and the plasma processing system according to the eleventhembodiment.

Now, the operation of the performance management system of thisembodiment will be described according to the flowchart in FIG. 35 andwith reference to FIGS. 15 and 17.

To start the performance evaluation using this system, a user of thisperformance management system, for example, a customer or a serviceengineer visiting the customer, measures a plasma electrode capacitanceC_(e1) and a loss capacitance C_(X1) of the plasma processing chamber ofthe plasma processing apparatus delivered to the customer site oralready put into operation at the customer site. The observed values areinput through a customer I/O device 220. When the performance managementsystem shown in FIG. 17 is used, the observed values are directly inputfrom a RF characteristic meter 260 connected to the plasma processingapparatus 250.

The input values of C_(X1) and C_(e1) are transmitted to a server 210via a communication line 230 (Step 301).

The server 210 then calculates C_(X1)/26 (Step 302), compares C_(X1)/26with the plasma electrode capacitance C_(e1), and evaluates theperformance of the plasma processing apparatus.

When C_(X1)/26 is less than the plasma electrode capacitance C_(e1),i.e., when C_(X1) is less than 26 times the plasma electrode capacitanceC_(e1), the server determines that the required level of performance ismaintained. When C_(X1)/26 is not less than the plasma electrodecapacitance C_(e1), i.e., when C_(X1) is not less than 26 times theplasma electrode capacitance C_(e1), the server determines that therequire level of performance is not maintained (Step 303).

In the plasma processing apparatus or system having a plurality ofplasma processing chambers according the ninth to eleventh embodiments,plural values of C_(X1) are input to the server. The server determinesthat the required level of performance is maintained only when C_(X1)/26is less than the plasma electrode capacitance C_(e1) in every plasmaprocessing chamber. The server otherwise determines that the requiredlevel of performance is not maintained.

Next, the server 210 provides the performance evaluation results to boththe customer I/O device 220 and an output device 240 located at thedelivery site (Step 304).

To the customer I/O device 220, a print command signal, display commandsignal, or a sound signal are transmitted. For example, a message “Thisplasma processing apparatus is maintained at the required performancelevel. Please continue using.” and a message “This plasma processingapparatus may not be maintained at the required performance level.Please adjust the apparatus according to the manual.” are conveyed tothe customer or the service engineer by printing, display on the screen,or sound when the server determines that the required level of theperformance is satisfied and that required level of the performance isnot satisfied, respectively.

The print command signal, the display command signal, the sound signal,a signal output signal, or a warning sound signal is also transmitted tothe output device 240 when the server 210 determines that the requiredperformance level is not satisfied. The output device 240 then eitherprints, displays, or outputs signals or a maintenance command such asalarm sound. In order to specify at the delivery site which apparatus orsystem at the customer site requires maintenance, the identificationnumber of the relevant plasma processing chamber is preferablytransmitted from the customer I/O device 220 and is preferably output atthe output device 240 located at the delivery site. Alternatively, theidentification number or phone number of the customer I/O device 220 maybe used to determine the identification number of the plasma processingchamber and to output the results from the output device 240.

Thus, a customer or a service engineer visiting the customer canimmediately evaluate the performance of the plasma processing apparatusaccording to Evaluation Standard 1 without actually operating the plasmaprocessing apparatus and then inspecting substrates on which thedeposition is performed.

Moreover, the plasma processing apparatus can be directly evaluated insitu in a shorter period of time instead of by a conventional two-stageevaluation requiring the steps of first depositing the substrate andthen evaluating the operation of the plasma processing apparatus usingthe deposited substrates. Generally, when the plasma processingapparatus is first installed, the plasma processing apparatus isevaluated by the method requiring deposition on substrates to determinethe process recipe for that plasma processing apparatus. Whereasconventional plasma processing apparatuses require evaluation of all theplasma processing chambers, such an evaluation needs to be performed inonly one plasma processing chamber in this embodiment since theradiofrequency characteristics of that chamber and the other chambersare maintained to be the same.

Accordingly, the performance of the plasma processing apparatus afterdelivery can be easily evaluated in a short period of time, and thecycle from detection of defects to performance of corrective action canbe shortened. Also, the cost for substrates for inspection, cost forprocessing the substrates for inspection, and labor cost for the workersinvolved in the adjustment work can be reduced.

Moreover, the malfunctioning of the plasma processing apparatus locatedat the customer site can be immediately detected by the supplier such asa manufacturer at its own location through the maintenance command.Thus, better repair service can be provided to the customer.

Thirteenth Embodiment

Now a performance management system for a plasma processing apparatusaccording to a thirteenth embodiment of the present invention will bedescribed with reference to the drawings.

FIG. 36 illustrates the configuration of the performance managementsystem for the plasma processing apparatus of this embodiment. FIG. 37is a flowchart showing steps of providing evaluation informationexecuted in the performance management system. In FIGS. 36 and 37, thecomponents identical to those shown in FIGS. 15, 16, and 35 are referredto by the same reference numerals and the descriptions thereof areomitted.

The performance management system shown in FIG. 36 includes a server210, a customer I/O device 270, a communication line 230 for linking theserver 210 to the customer I/O device 270, and an output device 240located at the delivery site and linked to the server 210. Themanagement system of this embodiment is for the plasma processingapparatus and system which include a plurality of plasma processingchambers, i.e., the plasma processing apparatus and system of the ninthto eleventh embodiments.

Referring to FIG. 36, the operation of this embodiment will now bedescribed according to the flowchart shown in FIG. 37.

To start the performance evaluation using this system, a user of thisperformance management system at a customer site, i.e., a customer or aservice engineer visiting the customer, inputs through the customer I/Odevice 270 the identification number S of the plasma processing chamberand the measured values of a plasma electrode capacitance C_(e1) and aloss capacitance C_(X1) as the radiofrequency characteristics of theplasma processing chambers of the plasma processing apparatus.

The identification number S, the plasma electrode capacitance C_(e1),and the loss capacitance C_(X1) are transmitted to the server 210 viathe communication line 230 (Step 401).

Alternatively, a RF characteristic meter connected to the plasmaprocessing apparatus may be kept connected to the customer I/O device270 so that the identification number S of the plasma processing chamberand the measured value of the loss capacitance C_(X1) as theradiofrequency characteristic of the plasma processing chamber areautomatically entered.

The server 210 then specifies the maximum value C_(e1max) and theminimum value C_(e1min) among the plasma electrode capacitances C_(e1)of these chambers and the identification numbers S of the relevantplasma processing chambers. The server 210 also specifies the maximumvalue C_(X1max) and the minimum value C_(X1min) among the losscapacitances C_(X1) of these chambers and the identification numbers Sof the relevant plasma processing chambers (Step 402).

Next, variations C_(e1r) and C_(X1r) defined byC_(e1r)=(C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)) andC_(X1r)=(C_(X1max)−C_(X1min))/(C_(X1max)+(C_(X1min)) are calculated(Step 403).

The server 210 then compares C_(e1r) with a predetermined value (upperlimit), for example, 0.1, to evaluate the performance of the plasmaprocessing apparatus. When C_(e1r) is less than the predetermined value,the server 210 determines that the plasma processing apparatus maintainsthe required performance level. When C_(e1r) is not less than thepredetermined value, the server 210 determines that the plasmaprocessing apparatus does not maintain the required performance level.The server 210 also compares C_(X1r) to a predetermined value, forexample, 0.1, to evaluate the performance of the plasma processingapparatus. When C_(X1r) is less than the predetermined value, the server210 determines that the plasma processing apparatus maintains therequired performance level. When C_(X1r) is not less than thepredetermined value, the server 210 determines that the plasmaprocessing apparatus does not maintain the required performance level(Step 404).

When the server 210 determines that the required performance level isnot satisfied, a maintenance command along with the maximum and minimumvalues C_(e1max), C_(e1min), C_(X1max), and C_(X1min) and theidentification numbers S of the relevant plasma processing chambers isprovided as the evaluation information to the output device 240 locatedat the delivery site (Step 405).

More particularly, the server 210 transmits a print command signal, adisplay signal, or an alarm sound signal to the output device 240. Themaintenance command and the identification numbers S of the relevantplasma processing chambers are output together so that the plasmaprocessing apparatus requiring maintenance can be specified at thedelivery site.

According to the performance management system for the plasma processingapparatus of this embodiment, a service engineer or the like at thedelivery site can readily identify the defective plasma processingchamber of the plasma processing apparatus.

More particularly, the service engineer or the like at the delivery sitesuch as a manufacturer or a maintenance company can readily evaluate theperformance of the plasma processing apparatus according to EvaluationStandard 2 without operating the plasma processing apparatus or systemalready delivered to the customer and then inspecting the processedsubstrates.

Moreover, the plasma processing apparatus or system can be directlyevaluated in situ in a shorter period of time instead of by aconventional two-stage evaluation requiring the steps of firstdepositing the substrate and then evaluating the operation of the plasmaprocessing apparatus using the deposited substrates. When an evaluationmethod requiring deposition on substrates is employed to determine theprocess recipe at the time of apparatus installation, such an evaluationneeds to be performed in only one plasma processing chamber since theradiofrequency characteristics of that chamber and other chambers aremaintained to be the same.

Accordingly, the performance of the plasma processing apparatus afterdelivery can be easily evaluated in a short period of time, and thecycle from detection of defects to performance of corrective action canbe shortened. Also, the cost for substrates for inspection, cost forprocessing the substrates for inspection, and labor cost for the workersinvolved in the adjustment work can be reduced.

Moreover, malfunctioning of the plasma processing apparatus at thecustomer site can be immediately detected by the manufacturer, etc., atthe delivery site through the maintenance command, providing betterrepair service to the customer.

EXAMPLES Comparative Example 1

A plasma processing apparatus of COMPARATIVE EXAMPLE 1 had the structureidentical to that shown in FIG. 11. The plasma electrode capacitanceC_(e) between the plasma excitation electrode 4 and the susceptorelectrode 8 was set at 25 pF, the loss capacitance C_(X) between theplasma excitation electrode 4 and the grounded positions was set at 980pF. The size of the parallel plate electrodes 4 and 8 was 25 cm square.The interelectrode distance was set at 30 mm. The power was set at 1,000W and a power frequency f_(e) was set at 40.68 MHz.

Example 1

A plasma processing apparatus of EXAMPLE 1 had the structure identicalto that of COMPARATIVE EXAMPLE 1. In EXAMPLE 1, the plasma electrodecapacitance C_(e) between the plasma excitation electrode 4 and thesusceptor electrode 8 was set at 37 pF by changing the interelectrodedistance to 20 mm. The loss capacitance C_(X) between the plasmaexcitation electrode 4 and the grounded positions was set at 980 pF soas to satisfy the relationship 26C_(e)>C_(X). The size of the parallelplate electrodes 4 and 8 was 25 cm square. The power was set at 1,000 Wand a power frequency f_(e) was set at 40.68 MHz.

Example 2

A plasma processing apparatus of EXAMPLE 2 had the structure identicalto that of EXAMPLE 1. In EXAMPLE 2, the loss capacitance C_(X) betweenthe plasma excitation electrode 4 and the grounded positions was set at250 pF by changing the overlapping area between the susceptor electrode8 and the upper chamber wall 10 a so as to satisfy the relationship7C_(e)>C_(X). The size of the parallel plate electrodes 4 and 8 was 25cm square. The power was set at 1,000 W and a power frequency f_(e) wasset at 40.68 MHz.

Example 3

A plasma processing apparatus of EXAMPLE 3 had the structure identicalto that of EXAMPLE 2. In EXAMPLE 3, the loss capacitance C_(X) betweenthe plasma excitation electrode 4 and the grounded positions was set at180 pF by changing the material characteristics of the insulatordisposed between the susceptor electrode 8 and the upper chamber wall 10a so as to satisfy the relationship 5C_(e)>C_(X). The size of theparallel plate electrodes 4 and 8 was 25 cm square. The power was set at800 W and a power frequency f_(e) was set at 40.68 MHz.

SiN_(X) layers were deposited at 800 W and 400 W in order to evaluatethe performance of the plasma processing apparatuses of EXAMPLES 1 to 3and COMPARATIVE EXAMPLE 1 as below.

(1) Deposition Rate and Planar Uniformity

The process for evaluating the deposition rate and the planar uniformityincluded the following:

Step 1: Depositing a SiN_(X) layer on a 6-inch glass substrate byplasma-enhanced CVD;

Step 2: Patterning a resist layer by photolithography;

Step 3: Dry-etching the SiN_(X) layer with SF₆ and O₂;

Step 4: Removing the resist layer by ashing with O₂;

Step 5: Measuring the layer thickness using a contact displacementmeter;

Step 6: Calculating the deposition rate from the deposition time and thelayer thickness; and

Step 7: Measuring the planar uniformity at 16 points on the substratesurface.

(2) BHF Etching Rate

Steps 1 and 2: Same as above;

Step 3: Immersing the substrate in a BHF solution (HF:NH₄F=1:10) at atemperature of 25° C. for one minute;

Step 4: Rinsing the substrate with deionized water, drying thesubstrate, and removing the resist layer with a mixture of sulfuric acidand hydrogen peroxide (H₂SO₄+H₂O₂);

Step 5: Measuring the unevenness as in Step 5 above; and

Step 6: Calculating the etching rate from the immersion time and theunevenness.

(3) Isolation Voltage

Step 1: Depositing a chromium layer on a glass substrate by sputteringand patterning the chromium layer to form a lower electrode;

Step 2: Depositing a SiN_(X) layer by plasma-enhanced CVD;

Step 3: Forming an upper electrode as in Step 1;

Step 4: Forming a contact hole for the lower electrode;

Step 5: Probing the upper and the lower electrodes to measure thecurrent-voltage characteristic (I-V characteristic) by varying thevoltage to approximately 200 V; and

Step 6: Defining the isolation voltage as the voltage V at 100 pAcorresponding to 1 μA/cm² in a 100 μm square electrode.

These results are shown in Table 2.

TABLE 2 COMPARATIVE EXAMPLE 1 EXAMPLE 1 EXAMPLE 2 EXAMPLE 3 Power output(W) 1,000 1,000 1,000 800 Loss capacitance C_(x) (pF) 980 980 250 180Plasma electrode 25 37 37 37 capacitance C_(e) (pF) Deposition rate(nm/min) 85 120 430 430 Planar uniformity (%) >±10 ≦±10 ≦±5 ≦±5 BHFetching rate (nm/min) >200 ≦200 ≦200 ≦200 Isolation voltage (MV/cm) ≦4≦4 ≦7 ≦7

These results show that the plasma processing apparatus of EXAMPLE 1satisfying 26C_(e)>C_(X) exhibits an improved deposition rate, planaruniformity, BHF etching rate, and isolation voltage. Compared toCOMPARATIVE EXAMPLE 1, the deposition rate is improved to more than 100nm/min, a variation in layer thickness is also improved, and the BHFetching rate is improved to 200 nm/min or less. The layercharacteristics are also improved. In the plasma processing apparatus ofEXAMPLE 2 satisfying 7C_(e)>C_(X), the deposition rate is improved byapproximately 5 times compared to COMPARATIVE EXAMPLE 1 and thevariation in layer thickness is improved to half the variation inEXAMPLE 1. The isolation voltage is also improved. In the plasmaprocessing apparatus of EXAMPLE 3 satisfying 5C_(e)>C_(X), the samelayer characteristics as that of EXAMPLE 2 can be obtained by using 80%output, i.e., even when the power is reduced from 1,000 W to 800 W.

Accordingly, the performance of the plasma processing apparatus isimproved by controlling the loss capacitance C_(X) between the plasmaexcitation electrode 4 and the ground potential positions.

The results fully demonstrates that the loss capacitance C_(X) betweenthe plasma excitation electrode 4 and the ground potential positions canbe used as the reference for the performance evaluation.

Example 4

A plasma processing apparatus of EXAMPLE 4 was of a multi-chamber typeand had the same structure as that shown in FIG. 30. In the plasmaprocessing apparatus of EXAMPLE 4, a variation C_(e1r) in the plasmaelectrode capacitance C_(e) defined by the relationshipC_(e1r)=(C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)) wherein C_(e1max) isthe maximum value and C_(e1min) is the minimum value among the plasmaelectrode capacitances C_(e1) of the plurality of plasma processingchambers measured after the delivery of the apparatus was set at 0.09.Moreover, a variation C_(X1r) in the loss capacitance C_(X) defined bythe relationship C_(X1r)=(C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min))wherein C_(X1max) is the maximum value and C_(X1min) is the minimumvalue among the loss capacitances C_(X1) of the plurality of plasmaprocessing chambers measured after the delivery of the apparatus wasalso set at 0.09.

The average plasma electrode capacitance C_(e) (the plasma electrodecapacitance C_(e1) measured after the delivery of the apparatus) was setto 37 pF and the average loss capacitance C_(X) (the loss capacitanceC_(X1) measured after the delivery of the apparatus) was set to 250 pF.

Example 5

A plasma processing apparatus of EXAMPLE 5 was of a multi-chamber typeand had the same structure as that shown in FIG. 30. In the plasmaprocessing apparatus of EXAMPLE 5, a variation C_(e1r) in the plasmaelectrode capacitance C_(e) among the values C_(e1) measured after thedelivery of the apparatus was set to 0.02, and a variation C_(X1r) inthe loss capacitance among the values C_(X1) measured after the deliveryof the apparatus was set to 0.02. The average plasma electrodecapacitance C_(e) (the plasma electrode capacitance C_(e1) measuredafter the delivery of the apparatus) was set to 37 pF and the averageloss capacitance C_(X) (the loss capacitance C_(X1) measured after thedelivery of the apparatus,) was set to 980 pF.

Comparative Example 2

A plasma processing apparatus of COMPARATIVE EXAMPLE 2 was of amulti-chamber type and had the same structure as that shown in FIG. 30.In the plasma processing apparatus of COMPARATIVE EXAMPLE 2, a variationC_(e1r) in the plasma electrode capacitance C_(e1) among the valuesC_(e1) measured after the delivery of the apparatus was set to 0.11, anda variation C_(X1r) in the loss capacitance among the values C_(X1)measured after the delivery of the apparatus was set to 0.11. Theaverage plasma electrode capacitance C_(e) (the plasma electrodecapacitance C_(e1) measured after the delivery of the apparatus) was setto 37 pF and the average loss capacitance C_(X) (the loss capacitanceC_(X1) measured after the delivery of the apparatus) was set to 180 pF.

The same process recipe was applied to the plasma processing apparatusesof EXAMPLES 4 and 5, and COMPARATIVE EXAMPLE 2 to deposit siliconnitride layers. A variation in the layer thickness among the plasmaprocessing chambers of each apparatus was measured as follows:

Step 1: Depositing a SiN_(X) layer on a 6-inch glass substrate byplasma-enhanced CVD;

Step 2: Patterning a resist layer by photolithography;

Step 3: Dry-etching the SiN_(X) layer with SF₆ and O₂;

Step 4: Removing the resist layer by ashing with O₂;

Step 5: Measuring the unevenness in the layer thickness using a contactdisplacement meter;

Step 6: Calculating the deposition rate from the deposition time and thelayer thickness; and

Step 7: Measuring the planar uniformity at 16 points on the substratesurface.

Herein, the layer was deposited under the following conditions:

Substrate temperature: 350° C.

SiH₄ flow rate: 40 SCCM

NH₃ flow rate: 200 SCCM

N₂ flow rate: 600 SCCM

Pressure: 150 Pa

The results are shown in Table 3.

TABLE 3 Variation in Variations in C_(e) Deposition Rate and C_(x)COMPARATIVE EXAMPLE 2 6.2% 0.11 EXAMPLE 4 4.9% 0.09 EXAMPLE 5 1.9% 0.02

The results show that the uniformity in the thickness of the layersdeposited in these plasma processing chambers is improved and theoperation of the plasma processing apparatus is improved by controllingthe variations C_(e1r) and C_(X1r) among the plasma electrodecapacitances C_(e1) and the loss capacitances C_(X1), respectively,measured after the delivery of the apparatus.

Thus, the variations in C_(e1) and C_(X1) can be used as the parameterfor the performance evaluation.

1. A performance evaluation method for a plasma processing apparatuscomprising: where the plasma processing apparatus is disassembled beforetransfer, is transported to a customer, and is reassembled at a customersite, the plasma processing apparatus including a plasma processingchamber including a plasma excitation electrode for exciting a plasma; aradiofrequency feeder, the plasma excitation electrode being connectedto the output end of the radiofrequency feeder; a radiofrequencygenerator for supplying a radiofrequency voltage to the plasmaexcitation electrode; and a matching circuit having an input terminaland an output terminal, the input terminal being connected to theradiofrequency generator and the output terminal being connected to theinput end of the radiofrequency feeder so as to achieve impedancematching between the plasma processing chamber and the radiofrequencygenerator, determining that the plasma processing apparatus maintains arequired level of performance when a loss capacitance C_(X1) of theplasma processing chamber after the delivery is less than 26 times aplasma electrode capacitance C_(e1) and that the plasma processingapparatus does not maintain the required level of performance when theloss capacitance C_(X1) is not less than 26 times the plasma electrodeloss capacitance C_(e1), wherein the loss capacitance C_(X1) is measuredbetween the plasma excitation electrode and pound potential positionswhich are DC-grounded and the plasma electrode capacitance C_(e1) ismeasured between the plasma excitation electrode and a counter electrodewhich generate a plasma in cooperation with each other.
 2. A performanceevaluation method for a plasma processing apparatus comprising: wherethe plasma processing apparatus is disassembled before transfer, istransported to a customer and is reassembled at a customer site, theplasma processing apparatus including a plurality of plasma processingchambers including plasma excitation electrodes for exciting plasma;radiofrequency feeders, each plasma excitation electrode being connectedto the output end of the corresponding radiofrequency feeder; at leastone radiofrequency generator for supplying a radiofrequency voltage tothe plasma excitation electrodes; and at least one matching circuithaving an input terminal and an output terminal, the input terminalbeing connected to the radiofrequency generator and the output terminalbeing connected to the input end of the radiofrequency feeder so as toachieve impedance matching between the plasma processing chambers andthe radiofrequency generator, determining that the plasma processingapparatus maintains a required level of performance when a variationC_(e1r), defined by (C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)), betweenthe maximum capacitance C_(e1max) and the minimum capacitance C_(e1min)among plasma electrode capacitances C_(e1) of the plurality of plasmaprocessing chambers is less than an upper limit and that the plasmaprocessing apparatus does not maintain the required level of performancewhen the variation is not less than the upper limit, wherein the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode and a counter electrode which generate a plasma in cooperationwith each other; and determining that the plasma processing apparatusmaintains a required level of performance when a variation C_(X1r),defined by (C_(X1max)−C_(X1min))/(C_(X1max)+C_(X) _(min)), between themaximum capacitance C_(X1max) and the minimum capacitance C_(X1min)among loss capacitances C_(X1) of the plurality of plasma processingchambers is less than an upper limit and that the plasma processingapparatus does not maintain the required level of performance when thevariation is not less than the upper limit, wherein the loss capacitanceC_(X1) is measured between the plasma excitation electrode and groundpotential positions which are DC-grounded.
 3. A performance evaluationmethod for a plasma processing apparatus according to claim 2, whereinboth the upper limits for the variation C_(e1r) and the variationC_(X1r) are 0.1.
 4. A performance evaluation method for a plasmaprocessing apparatus according to claim 2, wherein both the upper limitsfor the variation C_(e1r) and the variation C_(X1r) are 0.03.
 5. Aperformance evaluation method for a plasma processing apparatuscomprising: where the plasma processing apparatus is disassembled beforetransfer, is transported to a customer, and is reassembled at a customersite, the plasma processing apparatus including a plurality of plasmaprocessing chambers including plasma excitation electrodes for excitingplasma; radiofrequency feeders, each plasma excitation electrode beingconnected to the output end of the corresponding radiofrequency feeder;at least one radiofrequency generator for supplying a radiofrequencyvoltage to the plasma excitation electrodes; and at least one matchingcircuit having an input terminal and an output terminal, the inputterminal being connected to the radiofrequency generator and the outputterminal being connected to the input end of the radiofrequency feederso as to achieve impedance matching between the plasma processingchambers and the radiofrequency generator, determining than the plasmaprocessing apparatus maintains a required level of performance when avariation C_(e1r), defined by(C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)), between the maximumcapacitance C_(e1max) and the minimum capacitance C_(e1min) among plasmaelectrode capacitances C_(e1) of the plurality of plasma processingchambers is less than an upper limit and that the plasma processingapparatus does not maintain the required level of performance when thevariation is not less than the upper limit, wherein the plasma electrodecapacitance C_(e1) is measured between the plasma excitation electrodeand a counter electrode which generate a plasma in cooperation with eachother; and determining that the plasma processing apparatus maintains arequired level of performance when a variation C_(X1r), defined by(C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between the maximumcapacitance C_(X1max) and the minimum capacitance C_(X1min) among losscapacitances C_(X1) of the plurality of plasma processing chambers isless than an upper limit and when all the loss capacitances C_(X1) areless than 26 times the plasma electrode capacitance C_(e1) and that theplasma processing apparatus does not maintain the required level ofperformance when the variation is not less than the upper limit or whenone of the loss capacitances C_(X1) is not less than 26 times the plasmaelectrode capacitance C_(e1), wherein the loss capacitance C_(X1) ismeasured between the plasma excitation electrode and ground potentialpositions which are DC-grounded.
 6. A performance evaluation method fora plasma processing apparatus according to claim 5, wherein both theupper limits for the variation C_(e1r) variation C_(X1r) are 0.1.
 7. Aperformance evaluation method for a plasma processing apparatusaccording to claim 5, wherein the upper limits for the variation C_(e1r)the variation C_(X1r) are 0.03.
 8. A performance evaluation method for aplasma processing apparatus comprising: where the plasma processingsystem is disassembled before transfer, is transported to a customer,and is reassembled at a customer site, the plasma processing systemincluding a plurality of plasma processing apparatuses, each including aplasma processing chamber including a plasma excitation electrode forexciting a plasma; a radiofrequency feeder, the plasma excitationelectrode being connected to the output end of the radiofrequencyfeeder, a radiofrequency generator for supplying a radiofrequencyvoltage to the plasma excitation electrode; and a matching circuithaving an input terminal and an output terminal, the input terminalbeing connected to the radiofrequency generator and the output terminalbeing connected to the input and of the radiofrequency feeder so as toachieve impedance matching between the plasma processing chamber and theradiofrequency generator, determining that the plasma processing systemmaintains a required level of performance when a variation C_(e1r),defined by (C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)), between themaximum capacitance C_(e1max) and the minimum capacitance C_(e1min)among plasma electrode capacitances C_(e1) of the plurality of plasmaprocessing apparatuses is less than an upper limit and that the plasmaprocessing system does not maintain the required level of performancewhen the variation is net less than the upper limit, wherein the plasmaelectrode capacitance C_(e1) is measured between the plasma excitationelectrode and a counter electrode which generate a plasma in cooperationwith each other; and determining that the plasma processing systemmaintains a required level of performance when, a variation C_(X1r),defined by (C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between themaximum capacitance C_(X1max) and the minimum capacitance C_(X1min)among loss capacitances C_(X1) of the plurality of plasma processingapparatuses is less than an upper limit and that the plasma processingsystem does not maintain the required level of performance when thevariation is not less than the upper limit, wherein the loss capacitanceC_(X1) is measured between the plasma excitation electrode and groundpotential positions which are DC-grounded.
 9. A performance evaluationmethod for a plasma processing system according to claim 8, wherein boththe upper limits for the variation C_(e1r) and the variation C_(X1r) are0.1.
 10. A performance evaluation method for a plasma processing systemaccording to claim 8, wherein both the upper limits for the variationC_(e1r) and the variation C_(X1r) are 0.03.
 11. A performance evaluationmethod for a plasma processing apparatus comprising: where the plasmaprocessing system is disassembled before transfer, is transported to acustomer, and is reassembled at a customer site, the plasma processingsystem including a plurality of plasma processing apparatuses, eachincluding a plasma processing chamber including a plasma excitationelectrode for exciting a plasma; a radiofrequency feeder, the plasmaexcitation electrode being connected to the output end of theradiofrequency feeder, a radiofrequency generator for supplying aradiofrequency voltage to the plasma excitation electrode; and amatching circuit having an input terminal and an output terminal, theinput terminal being connected to the radiofrequency generator and theoutput terminal being connected to the input and of the radiofrequencyfeeder so as to achieve impedance matching between the plasma processingchamber and the radiofrequency generator, determining that the plasmaprocessing system maintains a required level of performance when avariation C_(e1r), defined by(C_(e1max)−C_(e1min))/(C_(e1max)+C_(e1min)), between the maximumcapacitance C_(e1max) and the minimum capacitance C_(e1min) among plasmaelectrode capacitances C_(e1) of the plurality of plasma processingapparatuses is less than an upper limit and that the plasma processingsystem does not maintain the required level of performance when thevariation is net less than the upper limit, wherein the plasma electrodecapacitance C_(e1) is measured between the plasma excitation electrodeand a counter electrode which generate a plasma in cooperation with eachother; and determining that the plasma processing system maintains arequired level of performance when a variation C_(X1r), defined by(C_(X1max)−C_(X1min))/(C_(X1max)+C_(X1min)), between the maximumcapacitance C_(X1max) and the minimum capacitance C_(X1min) among losscapacitances C_(X1) of the plurality of plasma processing chambers isless than an upper limit and when all loss capacitances C_(X1) are lessthan 26 times the plasma electrode capacitance C_(e1) and that theplasma processing apparatus does not maintain the required level ofperformance when the variation is not less than the upper limit, whereinthe loss capacitance C_(X1) is no less than 26 times the plasmaelectrode capacitance C_(e1), wherein the loss capacitance C_(X1) ispositions which are DC-grounded.
 12. A performance evaluation method fora plasma processing system according to claim 11, wherein both the upperlimits for the variation C_(e1r) and the variation C_(X1r) are 0.1. 13.A performance evaluation method for a plasma processing system accordingto claim 11, wherein both the upper limits for the variation C_(e1r) andthe variation C_(X1r) are 0.03.